On 6/22/11 1:49 PM, "Allen Wittenauer" <[email protected]> wrote:
> >On Jun 22, 2011, at 1:27 PM, Scott Carey wrote: > >> "Problems have been reported with Hadoop, the 64-bit JVM and Compressed >> Object References (the -XX:+UseCompressedOops option), so use of that >> option is discouraged." >> >> I think the above is dated. It also lacks critical information. What >>JVM >> and OS version was the problem seen? > >That is definitely dated. Those were problems from 18 and 19. > >> >> CompressedOops had several issues prior to Jre 6u20, and a few minor >>ones >> were fixed in u21. FWIW, I now exclusively use 64 bit w/ CompressedOops >> for all Hadoop and non-Hadoop apps and have seen no issues. It is the >> default in 6u24 and 6u25 on a 64 bit JVM. > > We use compressedoops on 21 every-so-often as well. > > Feel free to edit that whole section. :) > > Thanks! Updated the CompressedOops section. I am using 6u25 in production and have used 6u24 as well. (64 bit version, CentOS 5.5) We usually roll out JVM's to a subset of nodes, then after a little burn-in to the whole thing. First on development / qa clusters (which are just as busy as production, but smaller), then production. >
