Mercurial > hg
view tests/test-merge7.t @ 39561:d06834e0f48e
wireprotov2peer: stream decoded responses
Previously, wire protocol version 2 would buffer all response data.
Only once all data was received did we CBOR decode it and resolve
the future associated with the command. This was obviously not
desirable. In future commits that introduce large response payloads,
this caused significant memory bloat and slowed down client
operations due to waiting on the server.
This commit refactors the response handling code so that response
data can be streamed.
Command response objects now contain a buffered CBOR decoder. As
new data arrives, it is fed into the decoder. Decoded objects are
made available to the generator as they are decoded.
Because there is a separate thread processing incoming frames and
feeding data into the response object, there is the potential for
race conditions when mutating response objects. So a lock has been
added to guard access to critical state variables.
Because the generator emitting decoded objects needs to wait on
those objects to become available, we've added an Event for the
generator to wait on so it doesn't busy loop. This does mean
there is the potential for deadlocks. And I'm pretty sure they can
occur in some scenarios. We already have a handful of TODOs around
this. But I've added some more. Fixing this will likely require
moving the background thread receiving frames into clienthandler.
We likely would have done this anyway when implementing the client
bits for the SSH transport.
Test output changes because the initial CBOR map holding the overall
response state is now always handled internally by the response
object.
Differential Revision: https://phab.mercurial-scm.org/D4474
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Wed, 29 Aug 2018 15:17:11 -0700 |
parents | d4e62df1c73d |
children | 91a0bc50b288 |
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initial $ hg init test-a $ cd test-a $ cat >test.txt <<"EOF" > 1 > 2 > 3 > EOF $ hg add test.txt $ hg commit -m "Initial" clone $ cd .. $ hg clone test-a test-b updating to branch default 1 files updated, 0 files merged, 0 files removed, 0 files unresolved change test-a $ cd test-a $ cat >test.txt <<"EOF" > one > two > three > EOF $ hg commit -m "Numbers as words" change test-b $ cd ../test-b $ cat >test.txt <<"EOF" > 1 > 2.5 > 3 > EOF $ hg commit -m "2 -> 2.5" now pull and merge from test-a $ hg pull ../test-a pulling from ../test-a searching for changes adding changesets adding manifests adding file changes added 1 changesets with 1 changes to 1 files (+1 heads) new changesets 96b70246a118 (run 'hg heads' to see heads, 'hg merge' to merge) $ hg merge merging test.txt warning: conflicts while merging test.txt! (edit, then use 'hg resolve --mark') 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon [1] resolve conflict $ cat >test.txt <<"EOF" > one > two-point-five > three > EOF $ rm -f *.orig $ hg resolve -m test.txt (no more unresolved files) $ hg commit -m "Merge 1" change test-a again $ cd ../test-a $ cat >test.txt <<"EOF" > one > two-point-one > three > EOF $ hg commit -m "two -> two-point-one" pull and merge from test-a again $ cd ../test-b $ hg pull ../test-a pulling from ../test-a searching for changes adding changesets adding manifests adding file changes added 1 changesets with 1 changes to 1 files (+1 heads) new changesets 40d11a4173a8 (run 'hg heads' to see heads, 'hg merge' to merge) $ hg merge --debug searching for copies back to rev 1 resolving manifests branchmerge: True, force: False, partial: False ancestor: 96b70246a118, local: 50c3a7e29886+, remote: 40d11a4173a8 preserving test.txt for resolve of test.txt starting 4 threads for background file closing (?) test.txt: versions differ -> m (premerge) picked tool ':merge' for test.txt (binary False symlink False changedelete False) merging test.txt my test.txt@50c3a7e29886+ other test.txt@40d11a4173a8 ancestor test.txt@96b70246a118 test.txt: versions differ -> m (merge) picked tool ':merge' for test.txt (binary False symlink False changedelete False) my test.txt@50c3a7e29886+ other test.txt@40d11a4173a8 ancestor test.txt@96b70246a118 warning: conflicts while merging test.txt! (edit, then use 'hg resolve --mark') 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon [1] $ cat test.txt one <<<<<<< working copy: 50c3a7e29886 - test: Merge 1 two-point-five ======= two-point-one >>>>>>> merge rev: 40d11a4173a8 - test: two -> two-point-one three $ hg debugindex test.txt rev linkrev nodeid p1 p2 0 0 01365c4cca56 000000000000 000000000000 1 1 7b013192566a 01365c4cca56 000000000000 2 2 8fe46a3eb557 01365c4cca56 000000000000 3 3 fc3148072371 7b013192566a 8fe46a3eb557 4 4 d40249267ae3 8fe46a3eb557 000000000000 $ hg log changeset: 4:40d11a4173a8 tag: tip parent: 2:96b70246a118 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: two -> two-point-one changeset: 3:50c3a7e29886 parent: 1:d1e159716d41 parent: 2:96b70246a118 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Merge 1 changeset: 2:96b70246a118 parent: 0:b1832b9d912a user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Numbers as words changeset: 1:d1e159716d41 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: 2 -> 2.5 changeset: 0:b1832b9d912a user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Initial $ cd ..