On 4 January 2016 at 16:25, Philip Martin <philip.mar...@wandisco.com> wrote: > Branko Čibej <br...@apache.org> writes: > >> Your analysis looks sound, but I wonder if doing this would have any >> serious effect on checkout/update times; after all, the bulk of the work >> there is in report generation, only HTTPv2 is affected by GET response >> construction. > > When I checkout Subversion trunk from my local mirror I cannot measure a > client gain, but I can measure better server efficiency: > > - The CPU used by Apache goes down from 1.2s to 1.1s. > > - The number of system calls made by Apache goes down > > 68822 to 50664 for hot FSFS cache > 178885 to 161722 for cold FSFS cache > I'm getting similar results on Windows. svnbench null-export of 2000 15kb random files in 20 directories: Cold FSFS caches: CPU: 2028ms, IO Reads: 16350, Elapsed: 1374ms Hot FSFS caches: CPU: 1482ms, IO Reads: 9403, Elapsed: 1253ms
Patched: Cold FSFS caches: CPU: 1794ms, IO Reads: 14440, Elapsed: 1230ms Hot FSFS caches: CPU: 1263ms, IO Reads: 7787, Elapsed: 1184ms Elapsed is total execution time of svnbench null-export. CPU is processor used by server to serve client operation, IO reads is number of IO read operations of server process. So it's about 10% improvement in case of hot disk caches and local disk. Improvement could be more significant in case of network storage, spinning disks or high-load. I've also tested with 128 MB FSFS caches and full-text caching enabled: Baseline: Cold: CPU: 2028ms, IO Reads: 16028, Elapsed: 1643ms Hot: CPU: 1138ms, IO Reads: 2083, Elapsed: 1164ms Patched: Cold: CPU: 1934ms, IO Reads: 14028, Elapsed: 1473ms Hot: CPU: 1060ms, IO Reads: 83, Elapsed: 1059ms -- Ivan Zhakov
