On Mon, Dec 18, 2017 at 2:04 PM, Masahiko Sawada <sawada.m...@gmail.com> wrote: > On Sun, Dec 17, 2017 at 12:27 PM, Robert Haas <robertmh...@gmail.com> wrote: >> On Thu, Dec 14, 2017 at 5:45 AM, Masahiko Sawada <sawada.m...@gmail.com> >> wrote: >>> Here is the result. >>> I've measured the through-put with some cases on my virtual machine. >>> Each client loads 48k file to each different relations located on >>> either xfs filesystem or ext4 filesystem, for 30 sec. >>> >>> Case 1: COPYs to relations on different filessystems(xfs and ext4) and >>> N_RELEXTLOCK_ENTS is 1024 >>> >>> clients = 2, avg = 296.2068 >>> clients = 5, avg = 372.0707 >>> clients = 10, avg = 389.8850 >>> clients = 50, avg = 428.8050 >>> >>> Case 2: COPYs to relations on different filessystems(xfs and ext4) and >>> N_RELEXTLOCK_ENTS is 1 >>> >>> clients = 2, avg = 294.3633 >>> clients = 5, avg = 358.9364 >>> clients = 10, avg = 383.6945 >>> clients = 50, avg = 424.3687 >>> >>> And the result of current HEAD is following. >>> >>> clients = 2, avg = 284.9976 >>> clients = 5, avg = 356.1726 >>> clients = 10, avg = 375.9856 >>> clients = 50, avg = 429.5745 >>> >>> In case2, the through-put got decreased compare to case 1 but it seems >>> to be almost same as current HEAD. Because the speed of acquiring and >>> releasing extension lock got x10 faster than current HEAD as I >>> mentioned before, the performance degradation may not have gotten >>> decreased than I expected even in case 2. >>> Since my machine doesn't have enough resources the result of clients = >>> 50 might not be a valid result. >> >> I have to admit that result is surprising to me. >> > > I think the environment I used for performance measurement did not > have enough resources. I will do the same benchmark on an another > environment to see if it was a valid result, and will share it. >
I did performance measurement on an different environment where has 4 cores and physically separated two disk volumes. Also I've change the benchmarking so that COPYs load only 300 integer tuples which are not fit within single page, and changed tables to unlogged tables to observe the overhead of locking/unlocking relext locks. Case 1: COPYs to relations on different filessystems(xfs and ext4) and N_RELEXTLOCK_ENTS is 1024 clients = 1, avg = 3033.8933 clients = 2, avg = 5992.9077 clients = 4, avg = 8055.9515 clients = 8, avg = 8468.9306 clients = 16, avg = 7718.6879 Case 2: COPYs to relations on different filessystems(xfs and ext4) and N_RELEXTLOCK_ENTS is 1 clients = 1, avg = 3012.4993 clients = 2, avg = 5854.9966 clients = 4, avg = 7380.6082 clients = 8, avg = 7091.8367 clients = 16, avg = 7573.2904 And the result of current HEAD is following. clients = 1, avg = 2962.2416 clients = 2, avg = 5856.9774 clients = 4, avg = 7561.1376 clients = 8, avg = 7252.0192 clients = 16, avg = 7916.7651 As per the above results, compared with current HEAD the through-put of case 1 got increased up to 17%. On the other hand, the through-put of case 2 got decreased 2%~5%. Regards, -- Masahiko Sawada NIPPON TELEGRAPH AND TELEPHONE CORPORATION NTT Open Source Software Center
