On 4/7/22 16:48, Andrew Dunstan wrote: > On 4/7/22 13:10, Andres Freund wrote: >> Hi, >> >> On 2022-04-06 11:03:37 -0400, Andrew Dunstan wrote: >>> On 3/30/22 20:26, Andres Freund wrote: >>>> Could you try using dash to invoke configure here, and whether it makes >>>> configure faster? >>> I got weird failures re libxml/parser.h when I tried with dash. See >>> <https://cirrus-ci.com/task/5963254039052288> (It would be nice if we >>> could see config.log on failure.) >> Since dash won't help us to get the build time down sufficiently, and the >> tests don't pass without a separate build tree, I looked at what makes >> config/prep_buildtree so slow. >> >> It's largely just bad code. The slowest part are spawning one expr and mkdir >> -p for each directory. One 'cmp' for each makefile doesn't help either. >> >> The expr can be replaced with >> subdir=${item#$sourcetree} >> that's afaics posix syntax ([1]), not bash. >> >> Spawning one mkdir for each directory can be replaced by a single mkdir >> invocation with all the directories. On my linux workstation that gets the >> time for the first loop down from 1005ms to 38ms, really. >> >> That has the danger of the commandline getting too long. But since we rely on >> the final link of the backend to be done in a single command, I don't think >> it's making things worse? We could try to use xargs otherwise, iirc that's in >> posix as well. >> >> Using parameter substitution in the second loop takes it down from 775ms to >> 533ms. Not calling cmp when the file doesn't exist cuts it down to 337ms. >> >> I don't know of a way to batch the call to ln. The time with ln replaced with >> : is 151ms, fwiw. > > AFAIK Msy2s 'ln -s' by default copies a non-directory rather than > actually symlinking it. If we want real symlinks, then we need > MSYS=|winsymlinks:nativestrict set. The is will fail unless the calling > user is an Administrator or has the SeCreateSymbolicLink privilege. See > |
Sometimes I hate Thunderbird. Of course the | is spurious above, we would need MSYS=winsymlinks:nativestrict set. cheers andrew -- Andrew Dunstan EDB: https://www.enterprisedb.com
