Hi Daniel, I am getting 1200 conn/sec on very old hardware so maybe something else is wrong. The very first thing to do is to run logconv.pl script which will come installed with 389. It has a flag for recommendations which I suggest you enable or just enable every flag. Sample command: logconv.pl /var/log/dirsrv/slapd-<hostname>/access -efcibaltnxrgjyp I don't yet understand all the errors that this tool reports but it is a good start. One other thing, I disabled log buffering at one stage to debug something. I forgot about this and then ended up debugging why the server was so slow until I realized that is what I had done. So make sure you have logbuffering enabled. dn: cn=config changetype: modify replace: nsslapd-accesslog-logbuffering nsslapd-accesslog-logbuffering: on Regards > -----Original Message----- > From: 389-users-bounces@xxxxxxxxxxxxxxxxxxxxxxx [mailto:389-users- > bounces@xxxxxxxxxxxxxxxxxxxxxxx] On Behalf Of Daniel Fenert > Sent: 03 February 2011 16:30 > To: General discussion list for the 389 Directory server project. > Subject: [389-users] Performance tuning - where to begin? > > Hi, > > I have performance problem on 389-ds server and don't really know where > to start fine tuning. > > My current setup is master (2xQuadCore, 8GB RAM), few read-only slaves. > It works (more or less) without problems, but I would like to migrate to > multi master (2 master servers). > > To check if one master will handle the whole load, I've tried switching > clients from slaves to master one by one. > > After switching clients from third slave, I've encountered weird problem > - master was about 50% busy (looking at the cpu, no IO waits), but there was > problem with new connections. > Looking at the network level - there was SYN from client, but no ACK until > one or two retransmissions of SYN. > > I've tried increasing thread number (from 30 to 60), but problem still exists. > > The problem is near 400-500 connections/second. My whole load is > ~750conn/sec. Looking at the CPU usage, this server should handle the load. > It works stable with load ~300conn/sec. > > There are plenty of configuration options, where should I look first? > > -- > Daniel Fenert > -- > 389 users mailing list > 389-users@xxxxxxxxxxxxxxxxxxxxxxx > https://admin.fedoraproject.org/mailman/listinfo/389-users ________________________________________________________________________ In order to protect our email recipients, Betfair Group use SkyScan from MessageLabs to scan all Incoming and Outgoing mail for viruses. ________________________________________________________________________ -- 389 users mailing list 389-users@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/389-users