> From: Bob Liu [mailto:lliubbo@xxxxxxxxx] Subject: Re: [PATCHv13 3/4] zswap: add to mm/ > > On Thu, Jun 20, 2013 at 10:23 PM, Seth Jennings > <sjenning@xxxxxxxxxxxxxxxxxx> wrote: > > On Thu, Jun 20, 2013 at 05:42:04PM +0800, Bob Liu wrote: > >> > Just made a mmtests run of my own and got very different results: > >> > > >> > >> It's strange, I'll update to rc6 and try again. > >> By the way, are you using 824 hardware compressor instead of lzo? > > > > My results where using lzo software compression. > > > > Thanks, and today I used another machine to test zswap. > The total ram size of that machine is around 4G. > This time the result is better: > rc6 rc6 > zswap base > Ops memcachetest-0M 14619.00 ( 0.00%) 15602.00 ( 6.72%) > Ops memcachetest-435M 14727.00 ( 0.00%) 15860.00 ( 7.69%) > Ops memcachetest-944M 12452.00 ( 0.00%) 11812.00 ( -5.14%) > Ops memcachetest-1452M 12183.00 ( 0.00%) 9829.00 (-19.32%) > Ops memcachetest-1961M 11953.00 ( 0.00%) 9337.00 (-21.89%) > Ops memcachetest-2469M 11201.00 ( 0.00%) 7509.00 (-32.96%) > Ops memcachetest-2978M 9738.00 ( 0.00%) 5981.00 (-38.58%) > Ops io-duration-0M 0.00 ( 0.00%) 0.00 ( 0.00%) > Ops io-duration-435M 10.00 ( 0.00%) 6.00 ( 40.00%) > Ops io-duration-944M 19.00 ( 0.00%) 19.00 ( 0.00%) > Ops io-duration-1452M 31.00 ( 0.00%) 26.00 ( 16.13%) > Ops io-duration-1961M 40.00 ( 0.00%) 35.00 ( 12.50%) > Ops io-duration-2469M 45.00 ( 0.00%) 43.00 ( 4.44%) > Ops io-duration-2978M 58.00 ( 0.00%) 53.00 ( 8.62%) > Ops swaptotal-0M 56711.00 ( 0.00%) 8.00 ( 99.99%) > Ops swaptotal-435M 19218.00 ( 0.00%) 2101.00 ( 89.07%) > Ops swaptotal-944M 53233.00 ( 0.00%) 98055.00 (-84.20%) > Ops swaptotal-1452M 52064.00 ( 0.00%) 145624.00 (-179.70%) > Ops swaptotal-1961M 54960.00 ( 0.00%) 153907.00 (-180.03%) > Ops swaptotal-2469M 57485.00 ( 0.00%) 176340.00 (-206.76%) > Ops swaptotal-2978M 77704.00 ( 0.00%) 182996.00 (-135.50%) > Ops swapin-0M 24834.00 ( 0.00%) 8.00 ( 99.97%) > Ops swapin-435M 9038.00 ( 0.00%) 0.00 ( 0.00%) > Ops swapin-944M 26230.00 ( 0.00%) 42953.00 (-63.76%) > Ops swapin-1452M 25766.00 ( 0.00%) 68440.00 (-165.62%) > Ops swapin-1961M 27258.00 ( 0.00%) 68129.00 (-149.94%) > Ops swapin-2469M 28508.00 ( 0.00%) 82234.00 (-188.46%) > Ops swapin-2978M 37970.00 ( 0.00%) 89280.00 (-135.13%) > Ops minorfaults-0M 1460163.00 ( 0.00%) 927966.00 ( 36.45%) > Ops minorfaults-435M 954058.00 ( 0.00%) 936182.00 ( 1.87%) > Ops minorfaults-944M 972818.00 ( 0.00%) 1005956.00 ( -3.41%) > Ops minorfaults-1452M 966597.00 ( 0.00%) 1035465.00 ( -7.12%) > Ops minorfaults-1961M 976158.00 ( 0.00%) 1049441.00 ( -7.51%) > Ops minorfaults-2469M 967815.00 ( 0.00%) 1051752.00 ( -8.67%) > Ops minorfaults-2978M 988712.00 ( 0.00%) 1034615.00 ( -4.64%) > Ops majorfaults-0M 5899.00 ( 0.00%) 9.00 ( 99.85%) > Ops majorfaults-435M 2684.00 ( 0.00%) 67.00 ( 97.50%) > Ops majorfaults-944M 4380.00 ( 0.00%) 5790.00 (-32.19%) > Ops majorfaults-1452M 4161.00 ( 0.00%) 9222.00 (-121.63%) > Ops majorfaults-1961M 4435.00 ( 0.00%) 8800.00 (-98.42%) > Ops majorfaults-2469M 4555.00 ( 0.00%) 10541.00 (-131.42%) > Ops majorfaults-2978M 6182.00 ( 0.00%) 11618.00 (-87.93%) > > > But the performance of the first machine I used whose total ram size > is 2G is still bad. > I need more time to summarize those testing results. > > Maybe you can also have a try with lower total ram size. > > -- > Regards, > --Bob A very important factor that you are not considering and that might account for your different results is the "initial conditions". For example, I always ran my benchmarks after a default-configured EL6 boot, which launches many services at boot time, each of which creates many anonymous pages, and these "service anonymous pages" are often the pages that are selected by LRU for swapping, and compressed by zcache/zswap. Someone else may run the benchmarks on a minimally-configured embedded system, and someone else on a single-user system with no services running at all. A single-user system with no services is often best for reproducing benchmark results but may not be at all representative of the real world. At a minimum, it would be good to always record "Active(anon)" and "Inactive(anon)" in addition to the amount of physical RAM in the system. (Note, in /proc/meminfo on my system, the sum of these don't add up to "AnonPages"... I'm not sure why.) And of course, even if the number of anonymous pages is the same, the _contents_ of those pages may be very different, which will affect zcache/zswap density which may have a large impact on benchmark results. Thanks, Dan (T-minus two weeks and counting) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href