Re: (ITS#5985) replication lockout with syncrepl

[ando@sys-net.it]

quanah@OpenLDAP.org wrote:
> Full_Name: Quanah Gibson-Mount
> Version: 2.3/2.4/HEAD
> OS: Linux 2.6
> URL: ftp://ftp.openldap.org/incoming/
> Submission from: (NULL) (75.111.29.239)
> 
> 
> I noticed back in testing with OpenLDAP 2.3 that if a master gets a high rate of
> changes, and you have 3+ replicas, usually 2 replicas will end up getting all of
> the changes while the 3rd+ replicas have to wait until those 2 finish before
> getting changes.  If the high rate of changes goes on for a long enough period
> of time, this can cause the other replicas to get so far out of sync that it is
> more efficient to reload them than to wait on them to re-sync.  I discussed this
> with Howard, and in reviewing the code, he sees there's an underlying design
> issue with updates that is causing this.  His comments:
> 
> Once a thread for a psearch wakes up, it sends all the changes that were queued
> so it may hog an entire thread for a long time before the next psearch comes off
> the queue

Is this supposed to hit 2.4 as well, as you indicated in the ITS' "Version"?

p.


Ing. Pierangelo Masarati
OpenLDAP Core Team

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