Previously the file service client was a global object that all repos could
share. This was a bit hacky and is no longer needed. Now the file service
client exists per repo instance.
This is part of a series of changes to abstract the local caching and remote
file service in such a way that we can plug and play implementations.
If the memcache process exited early, remotefilelog was throwing an exception
instead of falling back to the server. This change makes it fall back to the
server, and also print a warning that the cache connection closed early.
Summary:
hg bundle was producing shallow bundles. This change makes it produce full
sized bundles so they can be used in other repos.
Test Plan: Added a test
Reviewers: sid0
Reviewed By: sid0
CC: keegancsmith
Differential Revision: https://phabricator.fb.com/D1167462
Summary:
Previously requesting remotefilelog file blobs from the server required write
access in order to write the blob to the cache. This changes it to not abort
entirely if the user doesn't have write access.
Test Plan:
cd tests
./run-tests.py --with-hg=/data/users/durham/hg/hg test-permissions.t
Also ran the test without the fix and verified it fails.
Reviewers: sid0, davidsp, pyd, dschleimer
Reviewed By: dschleimer
Differential Revision: https://phabricator.fb.com/D1145976
Task ID: 3601184
The remotecmd config is no longer necessary since we now use a dummy ssh. It
was also hardcoded for a specific filesystem structure, which didn't work on
other machines.
Summary:
Adds a 'hg prefetch' command to remotefilelog for prepopulating the
local cache. Supports specifying revsets and file patterns to limit what is
downloaded.
Test Plan: ./run-tests.py test-prefetch.t --with-hg=/data/users/durham/hg/hg
Reviewers: dschleimer, sid0, davidsp, pyd, mpm
CC: kunalb, minyoung
Differential Revision: https://phabricator.fb.com/D1129942
The alternate lookup code was mistakening looking for only the last digit
instead of looking at the entire prefix. This meant files with more than 10
alternates would start failing to find histories, which breaks rebase.
When falling back to the master server for cache misses, we only kept two
requests in flight at any time. Over high latency connections (like across
oceans) this resulted in very slow downloads.
This change increases the request size to 10,000 keys at once. This will keep
the size of the request lower than the tcp buffer size, while allowing us to
maximize our throughput.
Summary:
phrevset can hang when the revwalk already returns a rev but
the parallel arc call didn't finish with arc having subprocesses running.
This will result in hg log showing output but hanging for a quiet a bit.
We have to use a processgroup and make arc the leader of it to kill
all it's subprocesses properly. Note this will make it incompatible
with windows.
Test Plan:
Tested locally and ensured that a differential revision is
found and we abort nicely.
Reviewers: durham
Reviewed By: durham
Differential Revision: https://phabricator.fb.com/D1096568
Previously we sent the entire list of files to the fallback repo in a single ssh
write/flush. If the size of this write exceeded the tcp buffer on the receiving
end, the call would hang until the buffer had room. The problem is that the
receiving end (the server) is hung trying to send data back to the
client. Therefore it deadlocked.
The fix is to send and receive requests one at a time. We always have the next
request in flight while receiving so we shouldn't be waiting on requests too
often.
Enables specifying a name for a repo that is used in the cache key.
This allows multiple repos on a machine to share a cache without the
risk of keys overlapping.
Previously we used a global variable to track if the incoming connection was
from a shallow remote (based on if the network command was a *_shallow command).
This is hacky and overall a bad idea. The new implementation stores the shallow
flag as a bundlecapability passed to the getbundle command.
A side effect of this is remotefilelog won't work with versions of mercurial
that don't use the getbundle command.
The previous algorithm thought that if the system cache had the file rev, it was
guaranteed to be valid. This isn't true in the case of a machine in which
multiple people share the cache (one person may have pulled a rev but the other
hasn't).
The new algorithm is more explicit. It checks:
- system cache
- local cache
- local cache fallbacks
- remote cache
- master server
Adds a cache client implementation using the opensource python-memcached
library. It's more of an educational example than a production ready one since
it doesn't perform the requests asynchronously. It does however split up large
files into smaller chunks for you.
The remotefilelog extension currently doesn't work with tags. Adding include and
exclude patterns allows users to specify which files they want to treat as
shallow and which the want to download the entire history for. By excluding
.hgtags from being shallow, this enables tags to work in a mostly shallow repo.
This also enables largefile like scenarios where most files are full and only a
few large ones are kept remote.
A rare bug can occur where the local file blob might not exist, but a valid old
version of that blob does exist. This refactor the linknode logic in ancestormap
to check the old versions if the server fetch fails to find the blob.
It still prints an ugly warning message from the server, but this whole issue is
quite rare anyway.
When the cache is stored on a filesystem, excessive stat calls can slow
mercurial updates down dramatically. This reduces it to a single open call for
the cache location and if that fails, a single open call for the local location.
