Bug 1450684

Summary: Geo-replication delay cannot be configured to less than 3 seconds
Product: [Community] GlusterFS Reporter: nh2 <nh2-redhatbugzilla>
Component: geo-replicationAssignee: bugs <bugs>
Status: CLOSED EOL QA Contact:
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Version: 3.10CC: bugs, nh2-redhatbugzilla
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Last Closed: 2018-06-20 18:26:30 UTC Type: Bug
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Description nh2 2017-05-14 16:29:08 UTC 
Description of problem (on gluster 3.10.1):

It is impossible to configure geo-replication so that replication has low latency, even on links that have < 1ms latency.

Questions on how to improve the latency have come up in the past, for example:
http://lists.gluster.org/pipermail/gluster-users/2014-May/017272.html

Setting the volume option `rollover-time 1` improves the situation (it defaults to 15 seconds delay), but is not fully satisfying, as it can still take up to 3 seconds for a change to be reflected on replication slaves.

This is because gsyncd.py has an option

  op.add_option('--change-interval', metavar='SEC', type=int, default=3)

that defaults to 3 seconds and is not configurable from by the user.

Please make this setting configurable, so that users can set up low-latency geo replication.
Comment 1 Shyamsundar 2018-06-20 18:26:30 UTC 
This bug reported is against a version of Gluster that is no longer maintained (or has been EOL'd). See https://www.gluster.org/release-schedule/ for the versions currently maintained.

As a result this bug is being closed.

If the bug persists on a maintained version of gluster or against the mainline gluster repository, request that it be reopened and the Version field be marked appropriately.