On Mon, Jan 7, 2013 at 5:40 AM, Philip Martin <philip.mar...@wandisco.com> wrote: > Branko Čibej <br...@wandisco.com> writes: > >> Interesting that i's that much slower on the Mac. But considering my >> numbers: >> >> * FSFS: real 7m33.213s, user 19m8.075s, sys 10m54.739s >> * BDB: real 35m17.766s, user 15m28.395s, sys 11m58.824s >> >> Notice that the sys and user times are comparable, yet real-time is an >> order of magnitude higher with BDB. Also, in the FSFS case, real time is >> actually lower than user or sys time, which makes sense for parallel >> tests. I interpret that as meaning that FSFS parallelizes (across >> different processes) better than BDB, and that BDB spends most of its >> time twiddling its thumbs waiting for I/O. > > Given the Linux numbers the problem is OSX specific and not inherent to > BDB. Repository access in the testsuite is all single-thread and > single-process so any BDB locking should be trivial. If we don't drop > BDB then we shoud attempt to find out why BDB is slow on OSX.
I also think this is specific to OSX. I reported this problem several years ago on the list: http://svn.haxx.se/dev/archive-2008-04/0602.shtml As you can see from my email, the problem I was seeing seemed to be just in creating the repository. There was a significant time penalty and multiplied across the number of times the tests create repositories it really added up. I never figured out why this takes so long on OSX. I recall it was pretty easy to look at the tests.log and see where these unnatural delays existed. I recall it was mostly in setting up each new test, not the test itself. -- Thanks Mark Phippard http://markphip.blogspot.com/
