bdiff: use Python memory allocator in fixws
Python has its own memory allocation APIs. For allocations
<= 512 bytes, it allocates memory from arenas. This means that
average small allocations don't call the system allocator, which
makes them faster. Also, arena allocations cut down on memory
fragmentation, which can matter for performance in long-running
processes.
Another advantage of using the Python memory allocator is that
allocations are tracked by Python. This is a bigger deal in
Python 3, as modern versions of Python have some decent built-in
tools for examining memory usage, leaks, etc.
This patch converts a trivial malloc() + free() in the bdiff code
to use the Python allocator APIs. Since the object being
operated on is a line, chances are it will use an arena. So,
this could have a net positive impact on performance (although
I didn't measure it).
plain
$ hg init
$ hg debugbuilddag '+2:f +3:p2 @temp <f+4 @default /p2 +2' \
> --config extensions.progress= --config progress.assume-tty=1 \
> --config progress.delay=0 --config progress.refresh=0 \
> --config progress.format=topic,bar,number \
> --config progress.width=60
\r (no-eol) (esc)
building [ ] 0/12\r (no-eol) (esc)
building [ ] 0/12\r (no-eol) (esc)
building [==> ] 1/12\r (no-eol) (esc)
building [==> ] 1/12\r (no-eol) (esc)
building [======> ] 2/12\r (no-eol) (esc)
building [=========> ] 3/12\r (no-eol) (esc)
building [=============> ] 4/12\r (no-eol) (esc)
building [=============> ] 4/12\r (no-eol) (esc)
building [=============> ] 4/12\r (no-eol) (esc)
building [================> ] 5/12\r (no-eol) (esc)
building [====================> ] 6/12\r (no-eol) (esc)
building [=======================> ] 7/12\r (no-eol) (esc)
building [===========================> ] 8/12\r (no-eol) (esc)
building [===========================> ] 8/12\r (no-eol) (esc)
building [==============================> ] 9/12\r (no-eol) (esc)
building [==================================> ] 10/12\r (no-eol) (esc)
building [=====================================> ] 11/12\r (no-eol) (esc)
\r (no-eol) (esc)
tags
$ cat .hg/localtags
66f7d451a68b85ed82ff5fcc254daf50c74144bd f
bebd167eb94d257ace0e814aeb98e6972ed2970d p2
dag
$ hg debugdag -t -b
+2:f
+3:p2
@temp*f+3
@default*/p2+2:tip
tip
$ hg id
000000000000
glog
$ hg log -G --template '{rev}: {desc} [{branches}] @ {date}\n'
o 11: r11 [] @ 11.00
|
o 10: r10 [] @ 10.00
|
o 9: r9 [] @ 9.00
|\
| o 8: r8 [temp] @ 8.00
| |
| o 7: r7 [temp] @ 7.00
| |
| o 6: r6 [temp] @ 6.00
| |
| o 5: r5 [temp] @ 5.00
| |
o | 4: r4 [] @ 4.00
| |
o | 3: r3 [] @ 3.00
| |
o | 2: r2 [] @ 2.00
|/
o 1: r1 [] @ 1.00
|
o 0: r0 [] @ 0.00
overwritten files, starting on a non-default branch
$ rm -r .hg
$ hg init
$ hg debugbuilddag '@start.@default.:f +3:p2 @temp <f+4 @default /p2 +2' -q -o
tags
$ cat .hg/localtags
f778700ebd50fcf282b23a4446bd155da6453eb6 f
bbccf169769006e2490efd2a02f11c3d38d462bd p2
dag
$ hg debugdag -t -b
@start+1
@default+1:f
+3:p2
@temp*f+3
@default*/p2+2:tip
tip
$ hg id
000000000000
glog
$ hg log -G --template '{rev}: {desc} [{branches}] @ {date}\n'
o 11: r11 [] @ 11.00
|
o 10: r10 [] @ 10.00
|
o 9: r9 [] @ 9.00
|\
| o 8: r8 [temp] @ 8.00
| |
| o 7: r7 [temp] @ 7.00
| |
| o 6: r6 [temp] @ 6.00
| |
| o 5: r5 [temp] @ 5.00
| |
o | 4: r4 [] @ 4.00
| |
o | 3: r3 [] @ 3.00
| |
o | 2: r2 [] @ 2.00
|/
o 1: r1 [] @ 1.00
|
o 0: r0 [start] @ 0.00
glog of
$ hg log -G --template '{rev}: {desc} [{branches}]\n' of
o 11: r11 []
|
o 10: r10 []
|
o 9: r9 []
|\
| o 8: r8 [temp]
| |
| o 7: r7 [temp]
| |
| o 6: r6 [temp]
| |
| o 5: r5 [temp]
| |
o | 4: r4 []
| |
o | 3: r3 []
| |
o | 2: r2 []
|/
o 1: r1 []
|
o 0: r0 [start]
tags
$ hg tags -v
tip 11:9ffe238a67a2
p2 4:bbccf1697690 local
f 1:f778700ebd50 local
cat of
$ hg cat of --rev tip
r11
new and mergeable files
$ rm -r .hg
$ hg init
$ hg debugbuilddag '+2:f +3:p2 @temp <f+4 @default /p2 +2' -q -mn
dag
$ hg debugdag -t -b
+2:f
+3:p2
@temp*f+3
@default*/p2+2:tip
tip
$ hg id
000000000000
glog
$ hg log -G --template '{rev}: {desc} [{branches}] @ {date}\n'
o 11: r11 [] @ 11.00
|
o 10: r10 [] @ 10.00
|
o 9: r9 [] @ 9.00
|\
| o 8: r8 [temp] @ 8.00
| |
| o 7: r7 [temp] @ 7.00
| |
| o 6: r6 [temp] @ 6.00
| |
| o 5: r5 [temp] @ 5.00
| |
o | 4: r4 [] @ 4.00
| |
o | 3: r3 [] @ 3.00
| |
o | 2: r2 [] @ 2.00
|/
o 1: r1 [] @ 1.00
|
o 0: r0 [] @ 0.00
glog mf
$ hg log -G --template '{rev}: {desc} [{branches}]\n' mf
o 11: r11 []
|
o 10: r10 []
|
o 9: r9 []
|\
| o 8: r8 [temp]
| |
| o 7: r7 [temp]
| |
| o 6: r6 [temp]
| |
| o 5: r5 [temp]
| |
o | 4: r4 []
| |
o | 3: r3 []
| |
o | 2: r2 []
|/
o 1: r1 []
|
o 0: r0 []
man r4
$ hg manifest -r4
mf
nf0
nf1
nf2
nf3
nf4
cat r4 mf
$ hg cat -r4 mf
0 r0
1
2 r1
3
4 r2
5
6 r3
7
8 r4
9
10
11
12
13
14
15
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17
18
19
20
21
22
23
man r8
$ hg manifest -r8
mf
nf0
nf1
nf5
nf6
nf7
nf8
cat r8 mf
$ hg cat -r8 mf
0 r0
1
2 r1
3
4
5
6
7
8
9
10 r5
11
12 r6
13
14 r7
15
16 r8
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man
$ hg manifest --rev tip
mf
nf0
nf1
nf10
nf11
nf2
nf3
nf4
nf5
nf6
nf7
nf8
nf9
cat mf
$ hg cat mf --rev tip
0 r0
1
2 r1
3
4 r2
5
6 r3
7
8 r4
9
10 r5
11
12 r6
13
14 r7
15
16 r8
17
18 r9
19
20 r10
21
22 r11
23