diff options
| author | Eric Wong <e@yhbt.net> | 2020-08-25 10:51:20 +0000 |
|---|---|---|
| committer | Eric Wong <e@yhbt.net> | 2020-08-26 06:10:45 +0000 |
| commit | 78b1c973fba89bc6651ffa16807c40abd38e7bad (patch) | |
| tree | d344f2059b4dfa949f9e1b288417b19f85817365 /Documentation/public-inbox-init.pod | |
| parent | 9684e0406fd2c67706bc46e4c8e98a53c8edede3 (diff) | |
| download | public-inbox-78b1c973fba89bc6651ffa16807c40abd38e7bad.tar.gz | |
I've learned a thing or three about btrfs in the past few weeks and remembered some old HDD things, too. The Xapian MultiDatabase problem will need to be addressed for 1.7...
Diffstat (limited to 'Documentation/public-inbox-init.pod')
| -rw-r--r-- | Documentation/public-inbox-init.pod | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/Documentation/public-inbox-init.pod b/Documentation/public-inbox-init.pod index b25dd1e4..24645045 100644 --- a/Documentation/public-inbox-init.pod +++ b/Documentation/public-inbox-init.pod @@ -86,14 +86,21 @@ Default: unset, no epochs are skipped Control the number of Xapian index shards in a C<-V2> (L<public-inbox-v2-format(5)>) inbox. -It is useful to use a single shard (C<-j1>) for inboxes on +It can be useful to use a single shard (C<-j1>) for inboxes on high-latency storage (e.g. rotational HDD) unless the system has enough RAM to cache 5-10x the size of the git repository. -It is generally not useful to specify higher values than the -default due to contention in the top-level producer process. +Another approach for HDDs is to use the +L<public-inbox-index(1)/publicInbox.indexSequentialShard> option +and many shards, so each shard may fit into the kernel page +cache. Unfortunately, excessive shards slows down read-only +query performance. -Default: the number of online CPUs, up to 4 +For fast storage, it is generally not useful to specify higher +values than the default due to the top-level producer process +being a bottleneck. + +Default: the number of online CPUs, up to 4 (3 shard workers, 1 producer) =item --skip-docdata |