about summary refs log tree commit homepage
path: root/Documentation/public-inbox-index.pod
diff options
authorEric Wong <e@yhbt.net>2020-08-25 10:51:20 +0000
committerEric Wong <e@yhbt.net>2020-08-26 06:10:45 +0000
commit78b1c973fba89bc6651ffa16807c40abd38e7bad (patch)
treed344f2059b4dfa949f9e1b288417b19f85817365 /Documentation/public-inbox-index.pod
parent9684e0406fd2c67706bc46e4c8e98a53c8edede3 (diff)
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-index.pod')
1 files changed, 10 insertions, 2 deletions
diff --git a/Documentation/public-inbox-index.pod b/Documentation/public-inbox-index.pod
index 46a53825..207b2ed8 100644
--- a/Documentation/public-inbox-index.pod
+++ b/Documentation/public-inbox-index.pod
@@ -39,8 +39,12 @@ normal search functionality.
 Influences the number of Xapian indexing shards in a
 (L<public-inbox-v2-format(5)>) inbox.
+See L<public-inbox-init(1)/--jobs> for a full description
+of sharding.
 C<--jobs=0> is accepted as of public-inbox 1.6.0 (PENDING)
-to disable parallel indexing.
+to disable parallel indexing regardless of the number of
+pre-existing shards.
 If the inbox has not been indexed or initialized, C<JOBS - 1>
 shards will be created (one job is always needed for indexing
@@ -133,7 +137,11 @@ Available in public-inbox 1.6.0 (PENDING).
 =item --no-fsync
 Disables L<fsync(2)> and L<fdatasync(2)> operations on SQLite
-and Xapian.  This is only effective with Xapian 1.4+.
+and Xapian.  This is only effective with Xapian 1.4+.  This is
+primarily intended for systems with low RAM and the small
+(default) C<--batch-size=1m>.  Users of large C<--batch-size>
+may even find disabling L<fdatasync(2)> causes too much dirty
+data to accumulate, resulting on latency spikes from writeback.
 Available in public-inbox 1.6.0 (PENDING).