On Tue, Oct 12, 2010 at 11:06 PM, Abhijit Pol <[email protected]> wrote: > we did swapoff -a and then updated fstab to permanently turn it off.
You might not want to turn it off completely. One of the lads was recently talking about the horrors that can happen when no swap. But sounds like you were doing over eager swapping up to this? > we observed swap was actually happening on RSs and after we turned it off we > have much stable RSs. > > i can tell what we have, not sure that is optimal, in fact looking for > comments/suggestions from folks who have used it more: > 64GB RAM ==> 85% given to HBASE HEAP (30% memstore, 60%block cache) , 512MB > DN and 512MB TT > So, I'm bad at math, but thats a heap of 50+GB? Hows that working out for you? You played with GC tuning at all? You might give more to the DN and the TT since you have plenty -- and more to the OS... perhaps less to hbase? How many disks? > we have 64KB HDFS block size Do you mean 64MB? and 8K Hbase block size as our load is random > read dominated. > Small cells? If so, 8k can help some over having the 64k default. You've done the other stuff -- ulimits and xceivers? Hows it running for you? St.Ack
