From 3288d834a9a7f58d6a882e93656779ced3f72a7d Mon Sep 17 00:00:00 2001 From: Antonio SJ Musumeci Date: Tue, 23 Apr 2019 20:00:59 -0400 Subject: [PATCH] add reference to 32bit mmap kernel bug --- README.md | 9 ++++++++- man/mergerfs.1 | 8 +++++++- 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/README.md b/README.md index efa77ff6..02dfc234 100644 --- a/README.md +++ b/README.md @@ -1,6 +1,6 @@ % mergerfs(1) mergerfs user manual % Antonio SJ Musumeci -% 2019-03-21 +% 2019-04-23 # NAME @@ -674,6 +674,13 @@ Try enabling the `use_ino` option. Some have reported that it fixes the issue. Be sure to turn off `direct_io`. rtorrent and some other applications use [mmap](http://linux.die.net/man/2/mmap) to read and write to files and offer no failback to traditional methods. FUSE does not currently support mmap while using `direct_io`. There may be a performance penalty on writes with `direct_io` off as well as the problem of double caching but it's the only way to get such applications to work. If the performance loss is too high for other apps you can mount mergerfs twice. Once with `direct_io` enabled and one without it. Be sure to set `dropcacheonclose=true` if not using `direct_io`. +#### rtorrent fails with files >= 4GiB + +This is a kernel bug with mmap and FUSE on 32bit platforms. A fix should become available for all LTS releases. + +https://marc.info/?l=linux-fsdevel&m=155550785230874&w=2 + + #### Plex doesn't work with mergerfs It does. If you're trying to put Plex's config / metadata on mergerfs you have to leave `direct_io` off because Plex is using sqlite which apparently needs mmap. mmap doesn't work with `direct_io`. To fix this place the data elsewhere or disable `direct_io` (with `dropcacheonclose=true`). diff --git a/man/mergerfs.1 b/man/mergerfs.1 index aad6466b..203986a0 100644 --- a/man/mergerfs.1 +++ b/man/mergerfs.1 @@ -1,7 +1,7 @@ .\"t .\" Automatically generated by Pandoc 1.19.2.4 .\" -.TH "mergerfs" "1" "2019\-03\-21" "mergerfs user manual" "" +.TH "mergerfs" "1" "2019\-04\-23" "mergerfs user manual" "" .hy .SH NAME .PP @@ -1386,6 +1386,12 @@ mergerfs twice. Once with \f[C]direct_io\f[] enabled and one without it. Be sure to set \f[C]dropcacheonclose=true\f[] if not using \f[C]direct_io\f[]. +.SS rtorrent fails with files >= 4GiB +.PP +This is a kernel bug with mmap and FUSE on 32bit platforms. +A fix should become available for all LTS releases. +.PP +https://marc.info/?l=linux\-fsdevel&m=155550785230874&w=2 .SS Plex doesn\[aq]t work with mergerfs .PP It does.