how much does vmstat say is being used for cache? if it's not most of the other 14, then read I/O doesn't sound like the culprit
On Fri, Dec 4, 2009 at 4:17 PM, B. Todd Burruss <[email protected]> wrote: > thx for the tip. i've allocated -Xmx2G for cassandra out of 16G. > > > On Fri, 2009-12-04 at 14:22 -0600, Brandon Williams wrote: >> On Fri, Dec 4, 2009 at 1:40 PM, B. Todd Burruss <[email protected]> >> wrote: >> i've actually allocatted plenty of RAM, but it isn't fully >> used. the >> read performance dwindles well before reaching a RAM limit. >> >> >> You don't want to over-allocate memory to Cassandra, you want to leave >> as much free as you can so the OS can cache the reads for you. >> >> >> -Brandon >> > > >
