Friso, You may be knowing this already, but please bear in mind there is a potential risk of packets from previous connections that were in flight reach the new connections (that's the reason for the TIME_WAIT state in TCP).. And that may lead to unexpected behaviour..
Vidhya On 6/15/10 9:10 AM, "Jean-Daniel Cryans" <[email protected]> wrote: Friso, This is very interesting, and nobody answered probably because no one tried tcp_tw_recycle. I personally didn't even know about that config until a few minutes ago ;) So from the varnish mailing list, it seems that machines behind firewalls or NAT won't play well with that config, but I don't expect anyone running a cluster with that kind of setup... unless they are doing cross-DC or whatnot. http://www.mail-archive.com/[email protected]/msg02912.html Good stuff! J-D On Mon, Jun 14, 2010 at 11:40 PM, Friso van Vollenhoven <[email protected]> wrote: > Hi all, > > Since I got no replies to my previous message (see below), I went ahead and > set the tcp_tw_recycle to true. This worked like a charm. The number of > sockets in TIME_WAIT went down from many thousands to just a couple (tens). > Apparently, once set to true, the recycling happens quite eagerly. Most > importantly, the regionservers no longer shut down (which was the goal). I am > sharing the info here, just in case it might help someone sometime. > > > Cheers, > Friso > > > > On Jun 11, 2010, at 11:55 AM, Friso van Vollenhoven wrote: > >> Hi all, >> We are experiencing a lot of "java.net.BindException: Cannot assign >> requested address", which is a case of >> https://issues.apache.org/jira/browse/hbase-2492. At some point, all grinds >> to a halt and regionservers start to shut down. >> >> I was wondering if anyone has found a way around this problem (other than >> adding more machines to spread the load or reduce the work load). Has anyone >> been able to successfully apply the patch in >> https://issues.apache.org/jira/browse/HDFS-941 to 0.20.2? Or does anyone >> have experience with setting the /proc/sys/net/ipv4/tcp_tw_recycle to 1 >> (true) at the OS level? >> >> We are running HBase 0.20.4-2524, r941433 and Hadoop 0.20.2. >> >> Any experiences that anyone can share are greatly appreciated. >> >> >> Best regards, >> Friso >> > >
