Can someone who is having this issue try checking out the following git branch and rebuilding LZO?
https://github.com/toddlipcon/hadoop-lzo/tree/realloc This definitely stems one leak of a 64KB directbuffer on every reinit. -Todd On Wed, Jan 12, 2011 at 2:12 PM, Todd Lipcon <[email protected]> wrote: > Yea, you're definitely on the right track. Have you considered systems > programming, Friso? :) > > Hopefully should have a candidate patch to LZO later today. > > -Todd > > On Wed, Jan 12, 2011 at 1:20 PM, Friso van Vollenhoven < > [email protected]> wrote: > >> Hi, >> My guess is indeed that it has to do with using the reinit() method on >> compressors and making them long lived instead of throwaway together with >> the LZO implementation of reinit(), which magically causes NIO buffer >> objects not to be finalized and as a result not release their native >> allocations. It's just theory and I haven't had the time to properly verify >> this (unfortunately, I spend most of my time writing application code), but >> Todd said he will be looking into it further. I browsed the LZO code to see >> what was going on there, but with my limited knowledge of the HBase code it >> would be bald to say that this is for sure the case. It would be my first >> direction of investigation. I would add some logging to the LZO code where >> new direct byte buffers are created to log how often that happens and what >> size they are and then redo the workload that shows the leak. Together with >> some profiling you should be able to see how long it takes for these get >> finalized. >> >> Cheers, >> Friso >> >> >> >> On 12 jan 2011, at 20:08, Stack wrote: >> >> > 2011/1/12 Friso van Vollenhoven <[email protected]>: >> >> No, I haven't. But the Hadoop (mapreduce) LZO compression is not the >> problem. Compressing the map output using LZO works just fine. The problem >> is HBase LZO compression. The region server process is the one with the >> memory leak... >> >> >> > >> > (Sorry for dumb question Friso) But HBase is leaking because we make >> > use of the Compression API in a manner that produces leaks? >> > Thanks, >> > St.Ack >> >> > > > -- > Todd Lipcon > Software Engineer, Cloudera > -- Todd Lipcon Software Engineer, Cloudera
