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).
# init
$ hg init
$ echo a > a
$ hg add a
$ hg commit -m'a'
$ echo b > b
$ hg add b
$ hg commit -m'b'
$ hg up -C 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo c > c
$ hg add c
$ hg commit -m'c'
created new head
# test merging of diverged bookmarks
$ hg bookmark -r 1 "c@diverge"
$ hg bookmark -r 1 b
$ hg bookmark c
$ hg bookmarks
b 1:d2ae7f538514
* c 2:d36c0562f908
c@diverge 1:d2ae7f538514
$ hg merge "c@diverge"
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m'merge'
$ hg bookmarks
b 1:d2ae7f538514
* c 3:b8f96cf4688b
$ hg up -C 3
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
(leaving bookmark c)
$ echo d > d
$ hg add d
$ hg commit -m'd'
$ hg up -C 3
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo e > e
$ hg add e
$ hg commit -m'e'
created new head
$ hg up -C 5
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg bookmark e
$ hg bookmarks
b 1:d2ae7f538514
c 3:b8f96cf4688b
* e 5:26bee9c5bcf3
# the picked side is bookmarked
$ hg up -C 4
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
(leaving bookmark e)
$ hg merge
abort: heads are bookmarked - please merge with an explicit rev
(run 'hg heads' to see all heads)
[255]
# our revision is bookmarked
$ hg up -C e
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
(activating bookmark e)
$ hg merge
abort: no matching bookmark to merge - please merge with an explicit rev or bookmark
(run 'hg heads' to see all heads)
[255]
# merge bookmark heads
$ hg up -C 4
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
(leaving bookmark e)
$ echo f > f
$ hg commit -Am "f"
adding f
$ hg bookmarks -r 4 "e@diverged"
$ hg up -q -C "e@diverged"
$ hg merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg parents
changeset: 4:a0546fcfe0fb
bookmark: e@diverged
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: d
changeset: 5:26bee9c5bcf3
bookmark: e
parent: 3:b8f96cf4688b
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: e
$ hg up -C e
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
(activating bookmark e)
$ hg bookmarks
b 1:d2ae7f538514
c 3:b8f96cf4688b
* e 5:26bee9c5bcf3
e@diverged 4:a0546fcfe0fb
$ hg merge
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m'merge'
$ hg bookmarks
b 1:d2ae7f538514
c 3:b8f96cf4688b
* e 7:ca784329f0ba
# test warning when all heads are inactive bookmarks
$ hg up -C 6
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
(leaving bookmark e)
$ echo g > g
$ hg commit -Am 'g'
adding g
$ hg bookmark -i g
$ hg bookmarks
b 1:d2ae7f538514
c 3:b8f96cf4688b
e 7:ca784329f0ba
g 8:04dd21731d95
$ hg heads
changeset: 8:04dd21731d95
bookmark: g
tag: tip
parent: 6:be381d1126a0
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: g
changeset: 7:ca784329f0ba
bookmark: e
parent: 5:26bee9c5bcf3
parent: 4:a0546fcfe0fb
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: merge
$ hg merge
abort: heads are bookmarked - please merge with an explicit rev
(run 'hg heads' to see all heads)
[255]