diff --git a/README.md b/README.md index 1f32722d..5d840bfd 100644 --- a/README.md +++ b/README.md @@ -29,7 +29,7 @@ mergerfs -o<options> <srcmounts> <mountpoint> # OPTIONS -###options### +### mount options * **defaults**: a shortcut for FUSE's **atomic_o_trunc**, **auto_cache**, **big_writes**, **default_permissions**, **splice_move**, **splice_read**, and **splice_write**. These options seem to provide the best performance. * **direct_io**: causes FUSE to bypass caching which can increase write speeds at the detriment of reads. Note that not enabling `direct_io` will cause double caching of files and therefore less memory for caching generally. However, `mmap` does not work when `direct_io` is enabled. @@ -43,7 +43,7 @@ mergerfs -o<options> <srcmounts> <mountpoint> **NOTE:** Options are evaluated in the order listed so if the options are **func.rmdir=rand,category.action=ff** the **action** category setting will override the **rmdir** setting. -###srcmounts### +### srcmounts The srcmounts (source mounts) argument is a colon (':') delimited list of paths to be included in the pool. It does not matter if the paths are on the same or different drives nor does it matter the filesystem. Used and available space will not be duplicated for paths on the same device and any features which aren't supported by the underlying filesystem (such as file attributes or extended attributes) will return the appropriate errors. diff --git a/man/mergerfs.1 b/man/mergerfs.1 index 6cffd969..140e43a1 100644 --- a/man/mergerfs.1 +++ b/man/mergerfs.1 @@ -38,7 +38,7 @@ capacity) .IP \[bu] 2 Handles pool of readonly and read/write drives .SH OPTIONS -.SS options +.SS mount options .IP \[bu] 2 \f[B]defaults\f[]: a shortcut for FUSE\[aq]s \f[B]atomic_o_trunc\f[], \f[B]auto_cache\f[], \f[B]big_writes\f[], \f[B]default_permissions\f[], @@ -1024,15 +1024,28 @@ perscribe. .SS Why do I get an "out of space" error even though the system says there\[aq]s lots of space left? .PP -Please reread the sections above about policies, path preserving, and -the \f[B]moveonenospc\f[] option. +First make sure you\[aq]ve read the sections above about policies, path +preserving, and the \f[B]moveonenospc\f[] option. .PP Remember that mergerfs is simply presenting a logical merging of the contents of the pooled drives. -The reported free space is the aggregate space available \f[I]not\f[] +The reported free space is the aggregate space available \f[B]not\f[] the contiguous space available. +MergerFS does not split files across drives. If the writing of a file fills a drive and \f[B]moveonenospc\f[] is disabled it will return an ENOSPC error. +.PP +If \f[B]moveonenospc\f[] is enabled but there exists no drives with +enough space for the file and the data to be written (or the drive +happened to fill up as the file was being moved) it will error +indicating there isn\[aq]t enough space. +.PP +It is also possible that the filesystem selected has run out of inodes. +Use \f[C]df\ \-i\f[] to list the total and available inodes per +filesystem. +In the future it might be worth considering the number of inodes +available when making placement decisions in order to minimize this +situation. .SS Can mergerfs mounts be exported over NFS? .PP Yes.