Hi. You've almost described situation here - we've got several T2000s with 16GB of RAM and we're going ti implement in-software compression of some data. We're also thinking about raising arc.min and putting swap on a zvol with compression - it could be interesting once Adam will integrate gzip support into zfs.
The idea is - give ZFS for example minimum 5GB for its buffers, so syetm will start to swap earlier. Swap would be on zvol with compression=gzip. If we assume 3-5x compression of memory (we checked it with core files from our applications) then those 5GB will actually give us 15-25GB of memory. Of course there will be writes to disks but no reads (as long as we won't need more than 15-25GB of swap). At the and we had to dedicate 5GB but gained at least 15GB so we've won 10GB of additional memory. What do you think? I'm going to do simple tests on my laptop in a free time. ps. I'm not sure if ZFS bug which makes ZFS use only one CPU for all compression was fixed - it could affect performance. This message posted from opensolaris.org _______________________________________________ perf-discuss mailing list perf-discuss@opensolaris.org
