view tests/test-convert-p4.t @ 29787:80df04266a16

hgweb: profile HTTP requests

Currently, running `hg serve --profile` doesn't yield anything useful:
when the process is terminated the profiling output displays results
from the main thread, which typically spends most of its time in
select.select(). Furthermore, it has no meaningful results from
mercurial.* modules because the threads serving HTTP requests don't
actually get profiled.

This patch teaches the hgweb wsgi applications to profile individual
requests. If profiling is enabled, the profiler kicks in after
HTTP/WSGI environment processing but before Mercurial's main request
processing.

The profile results are printed to the configured profiling output.
If running `hg serve` from a shell, they will be printed to stderr,
just before the HTTP request line is logged. If profiling to a file,
we only write a single profile to the file because the file is not
opened in append mode. We could add support for appending to files
in a future patch if someone wants it.

Per request profiling doesn't work with the statprof profiler because
internally that profiler collects samples from the thread that
*initially* requested profiling be enabled. I have plans to address
this by vendoring Facebook's customized statprof and then improving
it.

#require p4

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "convert = " >> $HGRCPATH

create p4 depot
  $ P4ROOT=`pwd`/depot; export P4ROOT
  $ P4AUDIT=$P4ROOT/audit; export P4AUDIT
  $ P4JOURNAL=$P4ROOT/journal; export P4JOURNAL
  $ P4LOG=$P4ROOT/log; export P4LOG
  $ P4PORT=localhost:$HGPORT; export P4PORT
  $ P4DEBUG=1; export P4DEBUG

start the p4 server
  $ [ ! -d $P4ROOT ] && mkdir $P4ROOT
  $ p4d -f -J off >$P4ROOT/stdout 2>$P4ROOT/stderr &
  $ echo $! >> $DAEMON_PIDS
  $ trap "echo stopping the p4 server ; p4 admin stop" EXIT

  $ # wait for the server to initialize
  $ while ! p4 ; do
  >    sleep 1
  > done >/dev/null 2>/dev/null

create a client spec
  $ P4CLIENT=hg-p4-import; export P4CLIENT
  $ DEPOTPATH=//depot/test-mercurial-import/...
  $ p4 client -o | sed '/^View:/,$ d' >p4client
  $ echo View: >>p4client
  $ echo " $DEPOTPATH //$P4CLIENT/..." >>p4client
  $ p4 client -i <p4client
  Client hg-p4-import saved.

populate the depot
  $ echo a > a
  $ mkdir b
  $ echo c > b/c
  $ p4 add a b/c
  //depot/test-mercurial-import/a#1 - opened for add
  //depot/test-mercurial-import/b/c#1 - opened for add
  $ p4 submit -d initial
  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
  $ p4 edit a
  //depot/test-mercurial-import/a#1 - opened for edit
  $ echo aa >> a
  $ p4 submit -d "change a"
  Submitting change 2.
  Locking 1 files ...
  edit //depot/test-mercurial-import/a#2
  Change 2 submitted.

  $ p4 edit b/c
  //depot/test-mercurial-import/b/c#1 - opened for edit
  $ echo cc >> b/c
  $ p4 submit -d "change b/c"
  Submitting change 3.
  Locking 1 files ...
  edit //depot/test-mercurial-import/b/c#2
  Change 3 submitted.

convert
  $ hg convert -s p4 $DEPOTPATH dst
  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
  $ hg -R dst log --template 'rev={rev} desc="{desc}" tags="{tags}" files="{files}"\n'
  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
  $ p4 edit a b/c
  //depot/test-mercurial-import/a#2 - opened for edit
  //depot/test-mercurial-import/b/c#2 - opened for edit
  $ echo aaa >> a
  $ echo ccc >> b/c
  $ p4 submit -d "change a b/c"
  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
  $ hg convert -s p4 $DEPOTPATH dst
  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
  $ hg -R dst log --template 'rev={rev} desc="{desc}" tags="{tags}" files="{files}"\n'
  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
  $ echo dddd > "d d"
  $ mkdir " e"
  $ echo fff >" e/ f"
  $ p4 add "d d" " e/ f"
  //depot/test-mercurial-import/d d#1 - opened for add
  //depot/test-mercurial-import/ e/ f#1 - opened for add
  $ p4 submit -d "add d e f"
  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
  $ hg convert -s p4 $DEPOTPATH dst
  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
  $ hg -R dst log --template 'rev={rev} desc="{desc}" tags="{tags}" files="{files}"\n'
  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"

exit trap:
  stopping the p4 server