view tests/test-convert-p4.out @ 16363:2cdd7e63211b

parsers: incrementally parse the revlog index in C

We only parse entries in a revlog index file when they are actually
needed, and cache them when first requested.

This makes a huge difference to performance on large revlogs when
accessing the tip revision or performing a handful of numeric lookups
(very common cases).  For instance, "hg --time tip --template {node}"
on a tree with 300,000 revs takes 0.15 before, 0.02 after.

Even for revlog-intensive operations (e.g. running "hg log" to
completion), the lazy approach is about 1% faster than the eager
parse_index2.

% create p4 depot
% start the p4 server
% create a client spec
Client hg-p4-import saved.
% populate the depot
//depot/test-mercurial-import/a#1 - opened for add
//depot/test-mercurial-import/b/c#1 - opened for add
Submitting change 1.
Locking 2 files ...
add //depot/test-mercurial-import/a#1
add //depot/test-mercurial-import/b/c#1
Change 1 submitted.
% change some files
//depot/test-mercurial-import/a#1 - opened for edit
Submitting change 2.
Locking 1 files ...
edit //depot/test-mercurial-import/a#2
Change 2 submitted.
//depot/test-mercurial-import/b/c#1 - opened for edit
Submitting change 3.
Locking 1 files ...
edit //depot/test-mercurial-import/b/c#2
Change 3 submitted.
% convert
initializing destination dst repository
reading p4 views
collecting p4 changelists
1 initial
2 change a
3 change b/c
scanning source...
sorting...
converting...
2 initial
1 change a
0 change b/c
rev=2 desc="change b/c" tags="tip" files="b/c"
rev=1 desc="change a" tags="" files="a"
rev=0 desc="initial" tags="" files="a b/c"
% change some files
//depot/test-mercurial-import/a#2 - opened for edit
//depot/test-mercurial-import/b/c#2 - opened for edit
Submitting change 4.
Locking 2 files ...
edit //depot/test-mercurial-import/a#3
edit //depot/test-mercurial-import/b/c#3
Change 4 submitted.
% convert again
reading p4 views
collecting p4 changelists
1 initial
2 change a
3 change b/c
4 change a b/c
scanning source...
sorting...
converting...
0 change a b/c
rev=3 desc="change a b/c" tags="tip" files="a b/c"
rev=2 desc="change b/c" tags="" files="b/c"
rev=1 desc="change a" tags="" files="a"
rev=0 desc="initial" tags="" files="a b/c"
% interesting names
//depot/test-mercurial-import/d d#1 - opened for add
//depot/test-mercurial-import/ e/ f#1 - opened for add
Submitting change 5.
Locking 2 files ...
add //depot/test-mercurial-import/ e/ f#1
add //depot/test-mercurial-import/d d#1
Change 5 submitted.
% convert again
reading p4 views
collecting p4 changelists
1 initial
2 change a
3 change b/c
4 change a b/c
5 add d e f
scanning source...
sorting...
converting...
0 add d e f
rev=4 desc="add d e f" tags="tip" files=" e/ f d d"
rev=3 desc="change a b/c" tags="" files="a b/c"
rev=2 desc="change b/c" tags="" files="b/c"
rev=1 desc="change a" tags="" files="a"
rev=0 desc="initial" tags="" files="a b/c"
% stop the p4 server