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<h1>Package opt</h1>
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<dd><code>import "github.com/syndtr/goleveldb/leveldb/opt"</code></dd>
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<p>
Package opt provides sets of options used by LevelDB.
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<dd><a href="index.html#pkg-constants">Constants</a></dd>
<dd><a href="index.html#pkg-variables">Variables</a></dd>
<dd><a href="index.html#GetStrict">func GetStrict(o *Options, ro *ReadOptions, strict Strict) bool</a></dd>
<dd><a href="index.html#Cacher">type Cacher</a></dd>
<dd><a href="index.html#CacherFunc">type CacherFunc</a></dd>
<dd> <a href="index.html#CacherFunc.New">func (f *CacherFunc) New(capacity int) cache.Cacher</a></dd>
<dd><a href="index.html#Compression">type Compression</a></dd>
<dd> <a href="index.html#Compression.String">func (c Compression) String() string</a></dd>
<dd><a href="index.html#Options">type Options</a></dd>
<dd> <a href="index.html#Options.GetAltFilters">func (o *Options) GetAltFilters() []filter.Filter</a></dd>
<dd> <a href="index.html#Options.GetBlockCacheCapacity">func (o *Options) GetBlockCacheCapacity() int</a></dd>
<dd> <a href="index.html#Options.GetBlockCacher">func (o *Options) GetBlockCacher() Cacher</a></dd>
<dd> <a href="index.html#Options.GetBlockRestartInterval">func (o *Options) GetBlockRestartInterval() int</a></dd>
<dd> <a href="index.html#Options.GetBlockSize">func (o *Options) GetBlockSize() int</a></dd>
<dd> <a href="index.html#Options.GetCompactionExpandLimit">func (o *Options) GetCompactionExpandLimit(level int) int</a></dd>
<dd> <a href="index.html#Options.GetCompactionGPOverlaps">func (o *Options) GetCompactionGPOverlaps(level int) int</a></dd>
<dd> <a href="index.html#Options.GetCompactionL0Trigger">func (o *Options) GetCompactionL0Trigger() int</a></dd>
<dd> <a href="index.html#Options.GetCompactionSourceLimit">func (o *Options) GetCompactionSourceLimit(level int) int</a></dd>
<dd> <a href="index.html#Options.GetCompactionTableSize">func (o *Options) GetCompactionTableSize(level int) int</a></dd>
<dd> <a href="index.html#Options.GetCompactionTotalSize">func (o *Options) GetCompactionTotalSize(level int) int64</a></dd>
<dd> <a href="index.html#Options.GetComparer">func (o *Options) GetComparer() comparer.Comparer</a></dd>
<dd> <a href="index.html#Options.GetCompression">func (o *Options) GetCompression() Compression</a></dd>
<dd> <a href="index.html#Options.GetDisableBlockCache">func (o *Options) GetDisableBlockCache() bool</a></dd>
<dd> <a href="index.html#Options.GetDisableBufferPool">func (o *Options) GetDisableBufferPool() bool</a></dd>
<dd> <a href="index.html#Options.GetDisableCompactionBackoff">func (o *Options) GetDisableCompactionBackoff() bool</a></dd>
<dd> <a href="index.html#Options.GetDisableLargeBatchTransaction">func (o *Options) GetDisableLargeBatchTransaction() bool</a></dd>
<dd> <a href="index.html#Options.GetErrorIfExist">func (o *Options) GetErrorIfExist() bool</a></dd>
<dd> <a href="index.html#Options.GetErrorIfMissing">func (o *Options) GetErrorIfMissing() bool</a></dd>
<dd> <a href="index.html#Options.GetFilter">func (o *Options) GetFilter() filter.Filter</a></dd>
<dd> <a href="index.html#Options.GetIteratorSamplingRate">func (o *Options) GetIteratorSamplingRate() int</a></dd>
<dd> <a href="index.html#Options.GetNoSync">func (o *Options) GetNoSync() bool</a></dd>
<dd> <a href="index.html#Options.GetNoWriteMerge">func (o *Options) GetNoWriteMerge() bool</a></dd>
<dd> <a href="index.html#Options.GetOpenFilesCacheCapacity">func (o *Options) GetOpenFilesCacheCapacity() int</a></dd>
<dd> <a href="index.html#Options.GetOpenFilesCacher">func (o *Options) GetOpenFilesCacher() Cacher</a></dd>
<dd> <a href="index.html#Options.GetReadOnly">func (o *Options) GetReadOnly() bool</a></dd>
<dd> <a href="index.html#Options.GetStrict">func (o *Options) GetStrict(strict Strict) bool</a></dd>
<dd> <a href="index.html#Options.GetWriteBuffer">func (o *Options) GetWriteBuffer() int</a></dd>
<dd> <a href="index.html#Options.GetWriteL0PauseTrigger">func (o *Options) GetWriteL0PauseTrigger() int</a></dd>
<dd> <a href="index.html#Options.GetWriteL0SlowdownTrigger">func (o *Options) GetWriteL0SlowdownTrigger() int</a></dd>
<dd><a href="index.html#ReadOptions">type ReadOptions</a></dd>
<dd> <a href="index.html#ReadOptions.GetDontFillCache">func (ro *ReadOptions) GetDontFillCache() bool</a></dd>
<dd> <a href="index.html#ReadOptions.GetStrict">func (ro *ReadOptions) GetStrict(strict Strict) bool</a></dd>
<dd><a href="index.html#Strict">type Strict</a></dd>
<dd><a href="index.html#WriteOptions">type WriteOptions</a></dd>
<dd> <a href="index.html#WriteOptions.GetNoWriteMerge">func (wo *WriteOptions) GetNoWriteMerge() bool</a></dd>
<dd> <a href="index.html#WriteOptions.GetSync">func (wo *WriteOptions) GetSync() bool</a></dd>
</dl>
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<h4>Package files</h4>
<p>
<span style="font-size:90%">
<a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go">options.go</a>
</span>
</p>
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<div class="collapsed">
<h2 class="toggleButton" title="Click to show Internal Call Graph section">Internal call graph ▹</h2>
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<h2 class="toggleButton" title="Click to hide Internal Call Graph section">Internal call graph ▾</h2>
<p>
In the call graph viewer below, each node
is a function belonging to this package
and its children are the functions it
calls—perhaps dynamically.
</p>
<p>
The root nodes are the entry points of the
package: functions that may be called from
outside the package.
There may be non-exported or anonymous
functions among them if they are called
dynamically from another package.
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<p>
Click a node to visit that function's source code.
From there you can visit its callers by
clicking its declaring <code>func</code>
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<p>
Functions may be omitted if they were
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analyzed.
</p>
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</div> <!-- #pkg-callgraph -->
<h2 id="pkg-constants">Constants</h2>
<pre>const (
<span id="KiB">KiB</span> = 1024
<span id="MiB">MiB</span> = <a href="index.html#KiB">KiB</a> * 1024
<span id="GiB">GiB</span> = <a href="index.html#MiB">MiB</a> * 1024
)</pre>
<h2 id="pkg-variables">Variables</h2>
<pre>var (
<span id="DefaultBlockCacher">DefaultBlockCacher</span> = <a href="index.html#LRUCacher">LRUCacher</a>
<span id="DefaultBlockCacheCapacity">DefaultBlockCacheCapacity</span> = 8 * <a href="index.html#MiB">MiB</a>
<span id="DefaultBlockRestartInterval">DefaultBlockRestartInterval</span> = 16
<span id="DefaultBlockSize">DefaultBlockSize</span> = 4 * <a href="index.html#KiB">KiB</a>
<span id="DefaultCompactionExpandLimitFactor">DefaultCompactionExpandLimitFactor</span> = 25
<span id="DefaultCompactionGPOverlapsFactor">DefaultCompactionGPOverlapsFactor</span> = 10
<span id="DefaultCompactionL0Trigger">DefaultCompactionL0Trigger</span> = 4
<span id="DefaultCompactionSourceLimitFactor">DefaultCompactionSourceLimitFactor</span> = 1
<span id="DefaultCompactionTableSize">DefaultCompactionTableSize</span> = 2 * <a href="index.html#MiB">MiB</a>
<span id="DefaultCompactionTableSizeMultiplier">DefaultCompactionTableSizeMultiplier</span> = 1.0
<span id="DefaultCompactionTotalSize">DefaultCompactionTotalSize</span> = 10 * <a href="index.html#MiB">MiB</a>
<span id="DefaultCompactionTotalSizeMultiplier">DefaultCompactionTotalSizeMultiplier</span> = 10.0
<span id="DefaultCompressionType">DefaultCompressionType</span> = <a href="index.html#SnappyCompression">SnappyCompression</a>
<span id="DefaultIteratorSamplingRate">DefaultIteratorSamplingRate</span> = 1 * <a href="index.html#MiB">MiB</a>
<span id="DefaultOpenFilesCacher">DefaultOpenFilesCacher</span> = <a href="index.html#LRUCacher">LRUCacher</a>
<span id="DefaultOpenFilesCacheCapacity">DefaultOpenFilesCacheCapacity</span> = 500
<span id="DefaultWriteBuffer">DefaultWriteBuffer</span> = 4 * <a href="index.html#MiB">MiB</a>
<span id="DefaultWriteL0PauseTrigger">DefaultWriteL0PauseTrigger</span> = 12
<span id="DefaultWriteL0SlowdownTrigger">DefaultWriteL0SlowdownTrigger</span> = 8
)</pre>
<pre>var (
<span class="comment">// LRUCacher is the LRU-cache algorithm.</span>
<span id="LRUCacher">LRUCacher</span> = &<a href="index.html#CacherFunc">CacherFunc</a>{<a href="../cache/index.html">cache</a>.<a href="../cache/index.html#NewLRU">NewLRU</a>}
<span class="comment">// NoCacher is the value to disable caching algorithm.</span>
<span id="NoCacher">NoCacher</span> = &<a href="index.html#CacherFunc">CacherFunc</a>{}
)</pre>
<h2 id="GetStrict">func <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=18476:18539#L668">GetStrict</a></h2>
<pre>func GetStrict(o *<a href="index.html#Options">Options</a>, ro *<a href="index.html#ReadOptions">ReadOptions</a>, strict <a href="index.html#Strict">Strict</a>) <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h2 id="Cacher">type <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=1405:1462#L37">Cacher</a></h2>
<pre>type Cacher interface {
New(capacity <a href="../../../../../builtin/index.html#int">int</a>) <a href="../cache/index.html">cache</a>.<a href="../cache/index.html#Cacher">Cacher</a>
}</pre>
<p>
Cacher is a caching algorithm.
</p>
<h2 id="CacherFunc">type <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=1464:1531#L41">CacherFunc</a></h2>
<pre>type CacherFunc struct {
NewFunc func(capacity <a href="../../../../../builtin/index.html#int">int</a>) <a href="../cache/index.html">cache</a>.<a href="../cache/index.html#Cacher">Cacher</a>
}</pre>
<h3 id="CacherFunc.New">func (*CacherFunc) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=1533:1584#L45">New</a></h3>
<pre>func (f *<a href="index.html#CacherFunc">CacherFunc</a>) New(capacity <a href="../../../../../builtin/index.html#int">int</a>) <a href="../cache/index.html">cache</a>.<a href="../cache/index.html#Cacher">Cacher</a></pre>
<h2 id="Compression">type <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=1951:1972#L63">Compression</a></h2>
<pre>type Compression <a href="../../../../../builtin/index.html#uint">uint</a></pre>
<p>
Compression is the 'sorted table' block compression algorithm to use.
</p>
<pre>const (
<span id="DefaultCompression">DefaultCompression</span> <a href="index.html#Compression">Compression</a> = <a href="../../../../../builtin/index.html#iota">iota</a>
<span id="NoCompression">NoCompression</span>
<span id="SnappyCompression">SnappyCompression</span>
)</pre>
<h3 id="Compression.String">func (Compression) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=1974:2010#L65">String</a></h3>
<pre>func (c <a href="index.html#Compression">Compression</a>) String() <a href="../../../../../builtin/index.html#string">string</a></pre>
<h2 id="Options">type <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=4032:11043#L131">Options</a></h2>
<pre>type Options struct {
<span class="comment">// AltFilters defines one or more 'alternative filters'.</span>
<span class="comment">// 'alternative filters' will be used during reads if a filter block</span>
<span class="comment">// does not match with the 'effective filter'.</span>
<span class="comment">//</span>
<span class="comment">// The default value is nil</span>
AltFilters []<a href="../filter/index.html">filter</a>.<a href="../filter/index.html#Filter">Filter</a>
<span class="comment">// BlockCacher provides cache algorithm for LevelDB 'sorted table' block caching.</span>
<span class="comment">// Specify NoCacher to disable caching algorithm.</span>
<span class="comment">//</span>
<span class="comment">// The default value is LRUCacher.</span>
BlockCacher <a href="index.html#Cacher">Cacher</a>
<span class="comment">// BlockCacheCapacity defines the capacity of the 'sorted table' block caching.</span>
<span class="comment">// Use -1 for zero, this has same effect as specifying NoCacher to BlockCacher.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 8MiB.</span>
BlockCacheCapacity <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// BlockRestartInterval is the number of keys between restart points for</span>
<span class="comment">// delta encoding of keys.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 16.</span>
BlockRestartInterval <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// BlockSize is the minimum uncompressed size in bytes of each 'sorted table'</span>
<span class="comment">// block.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 4KiB.</span>
BlockSize <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// CompactionExpandLimitFactor limits compaction size after expanded.</span>
<span class="comment">// This will be multiplied by table size limit at compaction target level.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 25.</span>
CompactionExpandLimitFactor <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// CompactionGPOverlapsFactor limits overlaps in grandparent (Level + 2) that a</span>
<span class="comment">// single 'sorted table' generates.</span>
<span class="comment">// This will be multiplied by table size limit at grandparent level.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 10.</span>
CompactionGPOverlapsFactor <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// CompactionL0Trigger defines number of 'sorted table' at level-0 that will</span>
<span class="comment">// trigger compaction.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 4.</span>
CompactionL0Trigger <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// CompactionSourceLimitFactor limits compaction source size. This doesn't apply to</span>
<span class="comment">// level-0.</span>
<span class="comment">// This will be multiplied by table size limit at compaction target level.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 1.</span>
CompactionSourceLimitFactor <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// CompactionTableSize limits size of 'sorted table' that compaction generates.</span>
<span class="comment">// The limits for each level will be calculated as:</span>
<span class="comment">// CompactionTableSize * (CompactionTableSizeMultiplier ^ Level)</span>
<span class="comment">// The multiplier for each level can also fine-tuned using CompactionTableSizeMultiplierPerLevel.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 2MiB.</span>
CompactionTableSize <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// CompactionTableSizeMultiplier defines multiplier for CompactionTableSize.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 1.</span>
CompactionTableSizeMultiplier <a href="../../../../../builtin/index.html#float64">float64</a>
<span class="comment">// CompactionTableSizeMultiplierPerLevel defines per-level multiplier for</span>
<span class="comment">// CompactionTableSize.</span>
<span class="comment">// Use zero to skip a level.</span>
<span class="comment">//</span>
<span class="comment">// The default value is nil.</span>
CompactionTableSizeMultiplierPerLevel []<a href="../../../../../builtin/index.html#float64">float64</a>
<span class="comment">// CompactionTotalSize limits total size of 'sorted table' for each level.</span>
<span class="comment">// The limits for each level will be calculated as:</span>
<span class="comment">// CompactionTotalSize * (CompactionTotalSizeMultiplier ^ Level)</span>
<span class="comment">// The multiplier for each level can also fine-tuned using</span>
<span class="comment">// CompactionTotalSizeMultiplierPerLevel.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 10MiB.</span>
CompactionTotalSize <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// CompactionTotalSizeMultiplier defines multiplier for CompactionTotalSize.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 10.</span>
CompactionTotalSizeMultiplier <a href="../../../../../builtin/index.html#float64">float64</a>
<span class="comment">// CompactionTotalSizeMultiplierPerLevel defines per-level multiplier for</span>
<span class="comment">// CompactionTotalSize.</span>
<span class="comment">// Use zero to skip a level.</span>
<span class="comment">//</span>
<span class="comment">// The default value is nil.</span>
CompactionTotalSizeMultiplierPerLevel []<a href="../../../../../builtin/index.html#float64">float64</a>
<span class="comment">// Comparer defines a total ordering over the space of []byte keys: a 'less</span>
<span class="comment">// than' relationship. The same comparison algorithm must be used for reads</span>
<span class="comment">// and writes over the lifetime of the DB.</span>
<span class="comment">//</span>
<span class="comment">// The default value uses the same ordering as bytes.Compare.</span>
Comparer <a href="../comparer/index.html">comparer</a>.<a href="../comparer/index.html#Comparer">Comparer</a>
<span class="comment">// Compression defines the 'sorted table' block compression to use.</span>
<span class="comment">//</span>
<span class="comment">// The default value (DefaultCompression) uses snappy compression.</span>
Compression <a href="index.html#Compression">Compression</a>
<span class="comment">// DisableBufferPool allows disable use of util.BufferPool functionality.</span>
<span class="comment">//</span>
<span class="comment">// The default value is false.</span>
DisableBufferPool <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// DisableBlockCache allows disable use of cache.Cache functionality on</span>
<span class="comment">// 'sorted table' block.</span>
<span class="comment">//</span>
<span class="comment">// The default value is false.</span>
DisableBlockCache <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// DisableCompactionBackoff allows disable compaction retry backoff.</span>
<span class="comment">//</span>
<span class="comment">// The default value is false.</span>
DisableCompactionBackoff <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// DisableLargeBatchTransaction allows disabling switch-to-transaction mode</span>
<span class="comment">// on large batch write. If enable batch writes large than WriteBuffer will</span>
<span class="comment">// use transaction.</span>
<span class="comment">//</span>
<span class="comment">// The default is false.</span>
DisableLargeBatchTransaction <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// ErrorIfExist defines whether an error should returned if the DB already</span>
<span class="comment">// exist.</span>
<span class="comment">//</span>
<span class="comment">// The default value is false.</span>
ErrorIfExist <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// ErrorIfMissing defines whether an error should returned if the DB is</span>
<span class="comment">// missing. If false then the database will be created if missing, otherwise</span>
<span class="comment">// an error will be returned.</span>
<span class="comment">//</span>
<span class="comment">// The default value is false.</span>
ErrorIfMissing <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// Filter defines an 'effective filter' to use. An 'effective filter'</span>
<span class="comment">// if defined will be used to generate per-table filter block.</span>
<span class="comment">// The filter name will be stored on disk.</span>
<span class="comment">// During reads LevelDB will try to find matching filter from</span>
<span class="comment">// 'effective filter' and 'alternative filters'.</span>
<span class="comment">//</span>
<span class="comment">// Filter can be changed after a DB has been created. It is recommended</span>
<span class="comment">// to put old filter to the 'alternative filters' to mitigate lack of</span>
<span class="comment">// filter during transition period.</span>
<span class="comment">//</span>
<span class="comment">// A filter is used to reduce disk reads when looking for a specific key.</span>
<span class="comment">//</span>
<span class="comment">// The default value is nil.</span>
Filter <a href="../filter/index.html">filter</a>.<a href="../filter/index.html#Filter">Filter</a>
<span class="comment">// IteratorSamplingRate defines approximate gap (in bytes) between read</span>
<span class="comment">// sampling of an iterator. The samples will be used to determine when</span>
<span class="comment">// compaction should be triggered.</span>
<span class="comment">//</span>
<span class="comment">// The default is 1MiB.</span>
IteratorSamplingRate <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// NoSync allows completely disable fsync.</span>
<span class="comment">//</span>
<span class="comment">// The default is false.</span>
NoSync <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// NoWriteMerge allows disabling write merge.</span>
<span class="comment">//</span>
<span class="comment">// The default is false.</span>
NoWriteMerge <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// OpenFilesCacher provides cache algorithm for open files caching.</span>
<span class="comment">// Specify NoCacher to disable caching algorithm.</span>
<span class="comment">//</span>
<span class="comment">// The default value is LRUCacher.</span>
OpenFilesCacher <a href="index.html#Cacher">Cacher</a>
<span class="comment">// OpenFilesCacheCapacity defines the capacity of the open files caching.</span>
<span class="comment">// Use -1 for zero, this has same effect as specifying NoCacher to OpenFilesCacher.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 500.</span>
OpenFilesCacheCapacity <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// If true then opens DB in read-only mode.</span>
<span class="comment">//</span>
<span class="comment">// The default value is false.</span>
ReadOnly <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// Strict defines the DB strict level.</span>
Strict <a href="index.html#Strict">Strict</a>
<span class="comment">// WriteBuffer defines maximum size of a 'memdb' before flushed to</span>
<span class="comment">// 'sorted table'. 'memdb' is an in-memory DB backed by an on-disk</span>
<span class="comment">// unsorted journal.</span>
<span class="comment">//</span>
<span class="comment">// LevelDB may held up to two 'memdb' at the same time.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 4MiB.</span>
WriteBuffer <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// WriteL0StopTrigger defines number of 'sorted table' at level-0 that will</span>
<span class="comment">// pause write.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 12.</span>
WriteL0PauseTrigger <a href="../../../../../builtin/index.html#int">int</a>
<span class="comment">// WriteL0SlowdownTrigger defines number of 'sorted table' at level-0 that</span>
<span class="comment">// will trigger write slowdown.</span>
<span class="comment">//</span>
<span class="comment">// The default value is 8.</span>
WriteL0SlowdownTrigger <a href="../../../../../builtin/index.html#int">int</a>
}</pre>
<p>
Options holds the optional parameters for the DB at large.
</p>
<h3 id="Options.GetAltFilters">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=11045:11094#L352">GetAltFilters</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetAltFilters() []<a href="../filter/index.html">filter</a>.<a href="../filter/index.html#Filter">Filter</a></pre>
<h3 id="Options.GetBlockCacheCapacity">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=11343:11388#L368">GetBlockCacheCapacity</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetBlockCacheCapacity() <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetBlockCacher">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=11152:11193#L359">GetBlockCacher</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetBlockCacher() <a href="index.html#Cacher">Cacher</a></pre>
<h3 id="Options.GetBlockRestartInterval">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=11554:11601#L377">GetBlockRestartInterval</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetBlockRestartInterval() <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetBlockSize">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=11724:11760#L384">GetBlockSize</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetBlockSize() <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetCompactionExpandLimit">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=11850:11907#L391">GetCompactionExpandLimit</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetCompactionExpandLimit(level <a href="../../../../../builtin/index.html#int">int</a>) <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetCompactionGPOverlaps">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=12106:12162#L399">GetCompactionGPOverlaps</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetCompactionGPOverlaps(level <a href="../../../../../builtin/index.html#int">int</a>) <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetCompactionL0Trigger">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=12358:12404#L407">GetCompactionL0Trigger</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetCompactionL0Trigger() <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetCompactionSourceLimit">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=12524:12581#L414">GetCompactionSourceLimit</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetCompactionSourceLimit(level <a href="../../../../../builtin/index.html#int">int</a>) <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetCompactionTableSize">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=12780:12835#L422">GetCompactionTableSize</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetCompactionTableSize(level <a href="../../../../../builtin/index.html#int">int</a>) <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetCompactionTotalSize">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=13407:13464#L443">GetCompactionTotalSize</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetCompactionTotalSize(level <a href="../../../../../builtin/index.html#int">int</a>) <a href="../../../../../builtin/index.html#int64">int64</a></pre>
<h3 id="Options.GetComparer">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=14038:14087#L464">GetComparer</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetComparer() <a href="../comparer/index.html">comparer</a>.<a href="../comparer/index.html#Comparer">Comparer</a></pre>
<h3 id="Options.GetCompression">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=14185:14231#L471">GetCompression</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetCompression() <a href="index.html#Compression">Compression</a></pre>
<h3 id="Options.GetDisableBlockCache">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=14493:14538#L485">GetDisableBlockCache</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetDisableBlockCache() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="Options.GetDisableBufferPool">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=14381:14426#L478">GetDisableBufferPool</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetDisableBufferPool() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="Options.GetDisableCompactionBackoff">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=14605:14657#L492">GetDisableCompactionBackoff</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetDisableCompactionBackoff() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="Options.GetDisableLargeBatchTransaction">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=14731:14787#L499">GetDisableLargeBatchTransaction</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetDisableLargeBatchTransaction() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="Options.GetErrorIfExist">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=14865:14905#L506">GetErrorIfExist</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetErrorIfExist() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="Options.GetErrorIfMissing">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=14967:15009#L513">GetErrorIfMissing</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetErrorIfMissing() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="Options.GetFilter">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=15073:15116#L520">GetFilter</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetFilter() <a href="../filter/index.html">filter</a>.<a href="../filter/index.html#Filter">Filter</a></pre>
<h3 id="Options.GetIteratorSamplingRate">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=15170:15217#L527">GetIteratorSamplingRate</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetIteratorSamplingRate() <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetNoSync">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=15340:15374#L534">GetNoSync</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetNoSync() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="Options.GetNoWriteMerge">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=15430:15470#L541">GetNoWriteMerge</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetNoWriteMerge() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="Options.GetOpenFilesCacheCapacity">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=15739:15788#L558">GetOpenFilesCacheCapacity</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetOpenFilesCacheCapacity() <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetOpenFilesCacher">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=15532:15577#L548">GetOpenFilesCacher</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetOpenFilesCacher() <a href="index.html#Cacher">Cacher</a></pre>
<h3 id="Options.GetReadOnly">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=15970:16006#L567">GetReadOnly</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetReadOnly() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="Options.GetStrict">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=16064:16111#L574">GetStrict</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetStrict(strict <a href="index.html#Strict">Strict</a>) <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="Options.GetWriteBuffer">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=16216:16254#L581">GetWriteBuffer</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetWriteBuffer() <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetWriteL0PauseTrigger">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=16350:16396#L588">GetWriteL0PauseTrigger</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetWriteL0PauseTrigger() <a href="../../../../../builtin/index.html#int">int</a></pre>
<h3 id="Options.GetWriteL0SlowdownTrigger">func (*Options) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=16516:16565#L595">GetWriteL0SlowdownTrigger</a></h3>
<pre>func (o *<a href="index.html#Options">Options</a>) GetWriteL0SlowdownTrigger() <a href="../../../../../builtin/index.html#int">int</a></pre>
<h2 id="ReadOptions">type <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=16821:17245#L604">ReadOptions</a></h2>
<pre>type ReadOptions struct {
<span class="comment">// DontFillCache defines whether block reads for this 'read operation'</span>
<span class="comment">// should be cached. If false then the block will be cached. This does</span>
<span class="comment">// not affects already cached block.</span>
<span class="comment">//</span>
<span class="comment">// The default value is false.</span>
DontFillCache <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// Strict will be OR'ed with global DB 'strict level' unless StrictOverride</span>
<span class="comment">// is present. Currently only StrictReader that has effect here.</span>
Strict <a href="index.html#Strict">Strict</a>
}</pre>
<p>
ReadOptions holds the optional parameters for 'read operation'. The
'read operation' includes Get, Find and NewIterator.
</p>
<h3 id="ReadOptions.GetDontFillCache">func (*ReadOptions) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=17247:17293#L617">GetDontFillCache</a></h3>
<pre>func (ro *<a href="index.html#ReadOptions">ReadOptions</a>) GetDontFillCache() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="ReadOptions.GetStrict">func (*ReadOptions) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=17358:17410#L624">GetStrict</a></h3>
<pre>func (ro *<a href="index.html#ReadOptions">ReadOptions</a>) GetStrict(strict <a href="index.html#Strict">Strict</a>) <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h2 id="Strict">type <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=2308:2324#L85">Strict</a></h2>
<pre>type Strict <a href="../../../../../builtin/index.html#uint">uint</a></pre>
<p>
Strict is the DB 'strict level'.
</p>
<pre>const (
<span class="comment">// If present then a corrupted or invalid chunk or block in manifest</span>
<span class="comment">// journal will cause an error instead of being dropped.</span>
<span class="comment">// This will prevent database with corrupted manifest to be opened.</span>
<span id="StrictManifest">StrictManifest</span> <a href="index.html#Strict">Strict</a> = 1 << <a href="../../../../../builtin/index.html#iota">iota</a>
<span class="comment">// If present then journal chunk checksum will be verified.</span>
<span id="StrictJournalChecksum">StrictJournalChecksum</span>
<span class="comment">// If present then a corrupted or invalid chunk or block in journal</span>
<span class="comment">// will cause an error instead of being dropped.</span>
<span class="comment">// This will prevent database with corrupted journal to be opened.</span>
<span id="StrictJournal">StrictJournal</span>
<span class="comment">// If present then 'sorted table' block checksum will be verified.</span>
<span class="comment">// This has effect on both 'read operation' and compaction.</span>
<span id="StrictBlockChecksum">StrictBlockChecksum</span>
<span class="comment">// If present then a corrupted 'sorted table' will fails compaction.</span>
<span class="comment">// The database will enter read-only mode.</span>
<span id="StrictCompaction">StrictCompaction</span>
<span class="comment">// If present then a corrupted 'sorted table' will halts 'read operation'.</span>
<span id="StrictReader">StrictReader</span>
<span class="comment">// If present then leveldb.Recover will drop corrupted 'sorted table'.</span>
<span id="StrictRecovery">StrictRecovery</span>
<span class="comment">// This only applicable for ReadOptions, if present then this ReadOptions</span>
<span class="comment">// 'strict level' will override global ones.</span>
<span id="StrictOverride">StrictOverride</span>
<span class="comment">// StrictAll enables all strict flags.</span>
<span id="StrictAll">StrictAll</span> = <a href="index.html#StrictManifest">StrictManifest</a> | <a href="index.html#StrictJournalChecksum">StrictJournalChecksum</a> | <a href="index.html#StrictJournal">StrictJournal</a> | <a href="index.html#StrictBlockChecksum">StrictBlockChecksum</a> | <a href="index.html#StrictCompaction">StrictCompaction</a> | <a href="index.html#StrictReader">StrictReader</a> | <a href="index.html#StrictRecovery">StrictRecovery</a>
<span class="comment">// DefaultStrict is the default strict flags. Specify any strict flags</span>
<span class="comment">// will override default strict flags as whole (i.e. not OR'ed).</span>
<span id="DefaultStrict">DefaultStrict</span> = <a href="index.html#StrictJournalChecksum">StrictJournalChecksum</a> | <a href="index.html#StrictBlockChecksum">StrictBlockChecksum</a> | <a href="index.html#StrictCompaction">StrictCompaction</a> | <a href="index.html#StrictReader">StrictReader</a>
<span class="comment">// NoStrict disables all strict flags. Override default strict flags.</span>
<span id="NoStrict">NoStrict</span> = ^<a href="index.html#StrictAll">StrictAll</a>
)</pre>
<h2 id="WriteOptions">type <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=17606:18270#L633">WriteOptions</a></h2>
<pre>type WriteOptions struct {
<span class="comment">// NoWriteMerge allows disabling write merge.</span>
<span class="comment">//</span>
<span class="comment">// The default is false.</span>
NoWriteMerge <a href="../../../../../builtin/index.html#bool">bool</a>
<span class="comment">// Sync is whether to sync underlying writes from the OS buffer cache</span>
<span class="comment">// through to actual disk, if applicable. Setting Sync can result in</span>
<span class="comment">// slower writes.</span>
<span class="comment">//</span>
<span class="comment">// If false, and the machine crashes, then some recent writes may be lost.</span>
<span class="comment">// Note that if it is just the process that crashes (and the machine does</span>
<span class="comment">// not) then no writes will be lost.</span>
<span class="comment">//</span>
<span class="comment">// In other words, Sync being false has the same semantics as a write</span>
<span class="comment">// system call. Sync being true means write followed by fsync.</span>
<span class="comment">//</span>
<span class="comment">// The default value is false.</span>
Sync <a href="../../../../../builtin/index.html#bool">bool</a>
}</pre>
<p>
WriteOptions holds the optional parameters for 'write operation'. The
'write operation' includes Write, Put and Delete.
</p>
<h3 id="WriteOptions.GetNoWriteMerge">func (*WriteOptions) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=18272:18318#L654">GetNoWriteMerge</a></h3>
<pre>func (wo *<a href="index.html#WriteOptions">WriteOptions</a>) GetNoWriteMerge() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
<h3 id="WriteOptions.GetSync">func (*WriteOptions) <a href="http://localhost:6060/src/github.com/syndtr/goleveldb/leveldb/opt/options.go?s=18382:18420#L661">GetSync</a></h3>
<pre>func (wo *<a href="index.html#WriteOptions">WriteOptions</a>) GetSync() <a href="../../../../../builtin/index.html#bool">bool</a></pre>
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