Are you doing scans or are you doing get() with a known key? There's a big difference and scans are very expensive.
You also don't talk about your hardware. How much memory, how many cores per node, how you have your m/r configured (even if you're not running a m/r job, you still have to account for it.) There are so many things to look at.... > Subject: HBase reading performance > To: [email protected] > From: [email protected] > Date: Tue, 19 Jul 2011 08:21:26 +0800 > > > > Hi there, > HBase read performance works fine in most of the time, > but it took a very long time (over 500 seconds) yesterday while scan a few > records(it takes 2 seconds while HBase is normal) > I don't know how to do at that time; it lasted about 1 hour long, HBase > return to normal status. > So, my question is that any log or tool I can use it to know what's wrong > with HBase at that time. > I am afraid that compaction would do that great impact on read/write > performance. If so, any tunning I can do. > thank you. > > Our cluster with 20 machines > Hadoop 20 machines > Zookeeper 3 > RegionServer 10 > Hadoop version hadoop-0.20.2-cdh3u0 > HBase version hbase-0.90.1-cdh3u0 > > > > Fleming Chiu(邱宏明) > Ext: 707-2260 > Be Veg, Go Green, Save the Planet! > --------------------------------------------------------------------------- > TSMC PROPERTY > This email communication (and any attachments) is proprietary information > for the sole use of its > intended recipient. Any unauthorized review, use or distribution by anyone > other than the intended > recipient is strictly prohibited. If you are not the intended recipient, > please notify the sender by > replying to this email, and then delete this email and any copies of it > immediately. Thank you. > --------------------------------------------------------------------------- > > >
