That kind of complete pause/resume behavior most often happens from GC issues. How much heap are you giving to the stargate server? Also, try doing a thread dump during the lock-up time, maybe something telling there.
> -----Original Message----- > From: Andrew Purtell [mailto:[email protected]] > Sent: Tuesday, October 19, 2010 6:29 PM > To: [email protected]; [email protected] > Subject: Re: concurrency issue with Stargate/HTablePool > > Jeremy, > > Have you given any thought to trying out the latest 0.89 release? > > The Stargate package has been moved into org.apache.hadoop.hbase.rest > but otherwise it is the same. > > If this is a concurrency problem with the HBase client library it would > be better to try and deal with it on what is currently under > development, if you do not have a specific requirement to use 0.20.x. > > Best regards, > > - Andy > > > --- On Tue, 10/19/10, Jeremy Hinegardner <[email protected]> > wrote: > > > From: Jeremy Hinegardner <[email protected]> > > Subject: concurrency issue with Stargate/HTablePool > > To: [email protected] > > Date: Tuesday, October 19, 2010, 5:03 PM > > Hi all, > > > > I've done a bit of search on this issue, and have yet to > > find anything conclusive. As a test case to demonstrate it, > > I am using HBase 0.20.6 and stargate. > > > > I have a test HBase cluster with 1 table and about 60M rows > > in it, and a Stargate instance that talks to it. > > > > I have clients that queue up a random list of rowid's to > > query stargate via http://stargate.example.com:3002/table/rowid > > like requests. > > > > When I have 3 concurrent clients querying stargate, they > > all do well and get > > a consistent throughput. When I add the 4th client > > querying stargate, stargate > > comes to a screeching halt and everyone has 0 operations > > for a long while, then > > a small burst of requests will go through stargate and it > > will hang for a while, > > and repeat. > > > > If I then just kill one client, the other 3 start having a > > good consistent > > throughput again. Bring back the 4th client and it > > comes to a halt. > > > > If I bypass Stargate completely, and have all clients use > > HTable instances > > directly, then everyone is good. I can go up to as > > many clients as I need. > > > > This seems like quite a problem and I was wondering if > > anyone else is > > seeing something similar. > > > > thank you for your time, > > > > -jeremy > > > > > > -- > > > ======================================================================= > = > > Jeremy Hinegardner > > > > [email protected] > > > > > > > > >
