similar: sort files not by object id but by path for stable result
Perhaps the original implementation would want to sort added/removed files
alphabetically, but actually it did sort fctx objects by memory location.
This patch removes the use of set()s in order to preserve the order of
added/removed files. addedfiles.remove() becomes quadratic, but its cost
appears not dominant. Anyway, the quadratic behavior will be eliminated by
the next patch.
Benchmark with 50k added/removed files, on tmpfs:
$ mkdir src
$ for n in `seq 0 49`; do
> mkdir `printf src/%02d $n`
> done
$ for n in `seq 0 49999`; do
> f=`printf src/%02d/%05d $(($n/1000)) $n`
> dd if=/dev/urandom of=$f bs=8k count=1 status=none
> done
$ hg ci -qAm 'add 50k files of random content'
$ mv src dest
$ hg addremove --dry-run --time -q
original: real 16.550 secs (user 15.000+0.000 sys 1.540+0.000)
this patch: real 16.730 secs (user 15.280+0.000 sys 1.440+0.000)
Test how largefiles abort in case the disk runs full
$ cat > criple.py <<EOF
> import os, errno, shutil
> from mercurial import util
> #
> # this makes the original largefiles code abort:
> _origcopyfileobj = shutil.copyfileobj
> def copyfileobj(fsrc, fdst, length=16*1024):
> # allow journal files (used by transaction) to be written
> if 'journal.' in fdst.name:
> return _origcopyfileobj(fsrc, fdst, length)
> fdst.write(fsrc.read(4))
> raise IOError(errno.ENOSPC, os.strerror(errno.ENOSPC))
> shutil.copyfileobj = copyfileobj
> #
> # this makes the rewritten code abort:
> def filechunkiter(f, size=131072, limit=None):
> yield f.read(4)
> raise IOError(errno.ENOSPC, os.strerror(errno.ENOSPC))
> util.filechunkiter = filechunkiter
> #
> def oslink(src, dest):
> raise OSError("no hardlinks, try copying instead")
> util.oslink = oslink
> EOF
$ echo "[extensions]" >> $HGRCPATH
$ echo "largefiles =" >> $HGRCPATH
$ hg init alice
$ cd alice
$ echo "this is a very big file" > big
$ hg add --large big
$ hg commit --config extensions.criple=$TESTTMP/criple.py -m big
abort: No space left on device
[255]
The largefile is not created in .hg/largefiles:
$ ls .hg/largefiles
dirstate
The user cache is not even created:
>>> import os; os.path.exists("$HOME/.cache/largefiles/")
False
Make the commit with space on the device:
$ hg commit -m big
Now make a clone with a full disk, and make sure lfutil.link function
makes copies instead of hardlinks:
$ cd ..
$ hg --config extensions.criple=$TESTTMP/criple.py clone --pull alice bob
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
updating to branch default
getting changed largefiles
abort: No space left on device
[255]
The largefile is not created in .hg/largefiles:
$ ls bob/.hg/largefiles
dirstate