Re: Mingw task for Cirrus CI - Mailing list pgsql-hackers

Hi,

On 2022-10-11 11:23:36 -0700, Andres Freund wrote:
> > +  build_script:
> > +    - C:\msys64\usr\bin\dash.exe -lc "cd %CIRRUS_WORKING_DIR% && ninja -C %BUILD_DIR%"
> > +  upload_caches: ccache

Only remembered that just after sending my email: When using b_pch=true (which
saves a lot of time on mingw) ccache won't cache much (IIRC just the pch files
themselves) unless you do something like
export CCACHE_SLOPPINESS=pch_defines,time_macros

$ ccache -z -C
Clearing... 100.0% [==============================================================================]

$ ninja clean && ccache -z && CCACHE_SLOPPINESS= time ninja src/bin/pg_test_fsync/pg_test_fsync.exe && ccache -s
[2/2] Cleaning
Cleaning... 200 files.
Statistics zeroed
[124/124] Linking target src/bin/pg_test_fsync/pg_test_fsync.exe
0.00user 0.01system 0:07.60elapsed 0%CPU (0avgtext+0avgdata 4936maxresident)k
0inputs+0outputs (1314major+0minor)pagefaults 0swaps
Summary:
  Hits:               0 /    1 (0.00 %)
    Direct:           0 /    1 (0.00 %)
    Preprocessed:     0 /    1 (0.00 %)
  Misses:             1
    Direct:           1
    Preprocessed:     1
  Uncacheable:      110

As you can see, most of the files are determined to be unachable. The build
took 7.6s.


$ ninja clean && ccache -z && CCACHE_SLOPPINESS=pch_defines,time_macros time ninja
src/bin/pg_test_fsync/pg_test_fsync.exe&& ccache -s
 
[2/2] Cleaning
Cleaning... 200 files.
Statistics zeroed
[124/124] Linking target src/bin/pg_test_fsync/pg_test_fsync.exe
0.00user 0.01system 0:09.91elapsed 0%CPU (0avgtext+0avgdata 4936maxresident)k
0inputs+0outputs (1313major+0minor)pagefaults 0swaps
Summary:
  Hits:               0 /  111 (0.00 %)
    Direct:           0 /  111 (0.00 %)
    Preprocessed:     0 /  111 (0.00 %)
  Misses:           111
    Direct:         111
    Preprocessed:   111
Primary storage:
  Hits:               0 /  216 (0.00 %)
  Misses:           216
  Cache size (GB): 0.05 / 5.00 (0.98 %)

Files are cachable, but are cache misses (because we cleaned the cache
above). The build took 9.91s.


$ ninja clean && ccache -z && CCACHE_SLOPPINESS=pch_defines,time_macros time ninja
src/bin/pg_test_fsync/pg_test_fsync.exe&& ccache -s
 
[2/2] Cleaning
Cleaning... 200 files.
Statistics zeroed
[124/124] Linking target src/bin/pg_test_fsync/pg_test_fsync.exe
0.00user 0.01system 0:02.40elapsed 0%CPU (0avgtext+0avgdata 4936maxresident)k
0inputs+0outputs (1314major+0minor)pagefaults 0swaps
Summary:
  Hits:             111 /  111 (100.0 %)
    Direct:         111 /  111 (100.0 %)
    Preprocessed:     0 /    0
  Misses:             0
    Direct:           0
    Preprocessed:     0
Primary storage:
  Hits:             222 /  222 (100.0 %)
  Misses:             0
  Cache size (GB): 0.05 / 5.00 (0.98 %)

Files are cachable, and hit the cache. The build takes 2.4s.


Using ccache's depend mode reduce the cache-miss case to 7.51s and the cache
hit case to 1.75s. So we should likely export CCACHE_DEPEND=1 as well.

Greetings,

Andres Freund