util: lower water mark when removing nodes after cost limit reached
See the inline comment for the reasoning here. This is a pretty
common strategy for garbage collectors, other cache-like primtives.
The performance impact is substantial:
$ hg perflrucachedict --size 4 --gets 1000000 --sets 1000000 --mixed 1000000 --costlimit 100
! inserts w/ cost limit
! wall 1.659181 comb 1.650000 user 1.650000 sys 0.000000 (best of 7)
! wall 1.722122 comb 1.720000 user 1.720000 sys 0.000000 (best of 6)
! mixed w/ cost limit
! wall 1.139955 comb 1.140000 user 1.140000 sys 0.000000 (best of 9)
! wall 1.182513 comb 1.180000 user 1.180000 sys 0.000000 (best of 9)
$ hg perflrucachedict --size 1000 --gets 1000000 --sets 1000000 --mixed 1000000 --costlimit 10000
! inserts
! wall 0.679546 comb 0.680000 user 0.680000 sys 0.000000 (best of 15)
! sets
! wall 0.825147 comb 0.830000 user 0.830000 sys 0.000000 (best of 13)
! inserts w/ cost limit
! wall 25.105273 comb 25.080000 user 25.080000 sys 0.000000 (best of 3)
! wall 1.724397 comb 1.720000 user 1.720000 sys 0.000000 (best of 6)
! mixed
! wall 0.807096 comb 0.810000 user 0.810000 sys 0.000000 (best of 13)
! mixed w/ cost limit
! wall 12.104470 comb 12.070000 user 12.070000 sys 0.000000 (best of 3)
! wall 1.190563 comb 1.190000 user 1.190000 sys 0.000000 (best of 9)
$ hg perflrucachedict --size 1000 --gets 1000000 --sets 1000000 --mixed 1000000 --costlimit 10000 --mixedgetfreq 90
! inserts
! wall 0.711177 comb 0.710000 user 0.710000 sys 0.000000 (best of 14)
! sets
! wall 0.846992 comb 0.850000 user 0.850000 sys 0.000000 (best of 12)
! inserts w/ cost limit
! wall 25.963028 comb 25.960000 user 25.960000 sys 0.000000 (best of 3)
! wall 2.184311 comb 2.180000 user 2.180000 sys 0.000000 (best of 5)
! mixed
! wall 0.728256 comb 0.730000 user 0.730000 sys 0.000000 (best of 14)
! mixed w/ cost limit
! wall 3.174256 comb 3.170000 user 3.170000 sys 0.000000 (best of 4)
! wall 0.773186 comb 0.770000 user 0.770000 sys 0.000000 (best of 13)
$ hg perflrucachedict --size 100000 --gets 1000000 --sets 1000000 --mixed 1000000 --mixedgetfreq 90 --costlimit 5000000
! gets
! wall 1.191368 comb 1.190000 user 1.190000 sys 0.000000 (best of 9)
! wall 1.195304 comb 1.190000 user 1.190000 sys 0.000000 (best of 9)
! inserts
! wall 0.950995 comb 0.950000 user 0.950000 sys 0.000000 (best of 11)
! inserts w/ cost limit
! wall 1.589732 comb 1.590000 user 1.590000 sys 0.000000 (best of 7)
! sets
! wall 1.094941 comb 1.100000 user 1.090000 sys 0.010000 (best of 9)
! mixed
! wall 0.936420 comb 0.940000 user 0.930000 sys 0.010000 (best of 10)
! mixed w/ cost limit
! wall 0.882780 comb 0.870000 user 0.870000 sys 0.000000 (best of 11)
This puts us ~2x slower than caches without cost accounting. And for
read-heavy workloads (the prime use cases for caches), performance is
nearly identical.
In the worst case (pure write workloads with cost accounting enabled),
we're looking at ~1.5us per insert on large caches. That seems "fast
enough."
Differential Revision: https://phab.mercurial-scm.org/D4505
test sparse
$ hg init myrepo
$ cd myrepo
$ cat > .hg/hgrc <<EOF
> [extensions]
> sparse=
> purge=
> strip=
> rebase=
> EOF
Config file without [section] is rejected
$ cat > bad.sparse <<EOF
> *.html
> EOF
$ hg debugsparse --import-rules bad.sparse
abort: sparse config entry outside of section: *.html
(add an [include] or [exclude] line to declare the entry type)
[255]
$ rm bad.sparse
$ echo a > index.html
$ echo x > data.py
$ echo z > readme.txt
$ cat > webpage.sparse <<EOF
> # frontend sparse profile
> [include]
> *.html
> EOF
$ cat > backend.sparse <<EOF
> # backend sparse profile
> [include]
> *.py
> EOF
$ hg ci -Aqm 'initial'
$ hg debugsparse --include '*.sparse'
Verify enabling a single profile works
$ hg debugsparse --enable-profile webpage.sparse
$ ls
backend.sparse
index.html
webpage.sparse
Verify enabling two profiles works
$ hg debugsparse --enable-profile backend.sparse
$ ls
backend.sparse
data.py
index.html
webpage.sparse
Verify disabling a profile works
$ hg debugsparse --disable-profile webpage.sparse
$ ls
backend.sparse
data.py
webpage.sparse
Verify that a profile is updated across multiple commits
$ cat > webpage.sparse <<EOF
> # frontend sparse profile
> [include]
> *.html
> EOF
$ cat > backend.sparse <<EOF
> # backend sparse profile
> [include]
> *.py
> *.txt
> EOF
$ echo foo >> data.py
$ hg ci -m 'edit profile'
$ ls
backend.sparse
data.py
readme.txt
webpage.sparse
$ hg up -q 0
$ ls
backend.sparse
data.py
webpage.sparse
$ hg up -q 1
$ ls
backend.sparse
data.py
readme.txt
webpage.sparse
Introduce a conflicting .hgsparse change
$ hg up -q 0
$ cat > backend.sparse <<EOF
> # Different backend sparse profile
> [include]
> *.html
> EOF
$ echo bar >> data.py
$ hg ci -qAm "edit profile other"
$ ls
backend.sparse
index.html
webpage.sparse
Verify conflicting merge pulls in the conflicting changes
$ hg merge 1
temporarily included 2 file(s) in the sparse checkout for merging
merging backend.sparse
merging data.py
warning: conflicts while merging backend.sparse! (edit, then use 'hg resolve --mark')
warning: conflicts while merging data.py! (edit, then use 'hg resolve --mark')
0 files updated, 0 files merged, 0 files removed, 2 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
[1]
$ rm *.orig
$ ls
backend.sparse
data.py
index.html
webpage.sparse
Verify resolving the merge removes the temporarily unioned files
$ cat > backend.sparse <<EOF
> # backend sparse profile
> [include]
> *.html
> *.txt
> EOF
$ hg resolve -m backend.sparse
$ cat > data.py <<EOF
> x
> foo
> bar
> EOF
$ hg resolve -m data.py
(no more unresolved files)
$ hg ci -qAm "merge profiles"
$ ls
backend.sparse
index.html
readme.txt
webpage.sparse
$ hg cat -r . data.py
x
foo
bar
Verify stripping refreshes dirstate
$ hg strip -q -r .
$ ls
backend.sparse
index.html
webpage.sparse
Verify rebase conflicts pulls in the conflicting changes
$ hg up -q 1
$ ls
backend.sparse
data.py
readme.txt
webpage.sparse
$ hg rebase -d 2
rebasing 1:a2b1de640a62 "edit profile"
temporarily included 2 file(s) in the sparse checkout for merging
merging backend.sparse
merging data.py
warning: conflicts while merging backend.sparse! (edit, then use 'hg resolve --mark')
warning: conflicts while merging data.py! (edit, then use 'hg resolve --mark')
unresolved conflicts (see hg resolve, then hg rebase --continue)
[1]
$ rm *.orig
$ ls
backend.sparse
data.py
index.html
webpage.sparse
Verify resolving conflict removes the temporary files
$ cat > backend.sparse <<EOF
> [include]
> *.html
> *.txt
> EOF
$ hg resolve -m backend.sparse
$ cat > data.py <<EOF
> x
> foo
> bar
> EOF
$ hg resolve -m data.py
(no more unresolved files)
continue: hg rebase --continue
$ hg rebase -q --continue
$ ls
backend.sparse
index.html
readme.txt
webpage.sparse
$ hg cat -r . data.py
x
foo
bar
Test checking out a commit that does not contain the sparse profile. The
warning message can be suppressed by setting missingwarning = false in
[sparse] section of your config:
$ hg debugsparse --reset
$ hg rm *.sparse
$ hg commit -m "delete profiles"
$ hg up -q ".^"
$ hg debugsparse --enable-profile backend.sparse
$ ls
index.html
readme.txt
$ hg up tip | grep warning
warning: sparse profile 'backend.sparse' not found in rev bfcb76de99cc - ignoring it
[1]
$ ls
data.py
index.html
readme.txt
$ hg debugsparse --disable-profile backend.sparse | grep warning
warning: sparse profile 'backend.sparse' not found in rev bfcb76de99cc - ignoring it
[1]
$ cat >> .hg/hgrc <<EOF
> [sparse]
> missingwarning = false
> EOF
$ hg debugsparse --enable-profile backend.sparse
$ cd ..
#if unix-permissions
Test file permissions changing across a sparse profile change
$ hg init sparseperm
$ cd sparseperm
$ cat > .hg/hgrc <<EOF
> [extensions]
> sparse=
> EOF
$ touch a b
$ cat > .hgsparse <<EOF
> [include]
> a
> EOF
$ hg commit -Aqm 'initial'
$ chmod a+x b
$ hg commit -qm 'make executable'
$ cat >> .hgsparse <<EOF
> b
> EOF
$ hg commit -qm 'update profile'
$ hg up -q 0
$ hg debugsparse --enable-profile .hgsparse
$ hg up -q 2
$ ls -l b
-rwxr-xr-x* b (glob)
#endif