Shares are still verified in parallel, but within a share, don't request a
block until the previous block has been verified and the memory we used to hold
it has been freed up.
Patch originally due to Brian. This version has a mockery-patchery-style test
which is "low tech" (it implements the patching inline in the test code instead
of using an extension of the mock.patch() function from the mock library) and
which unpatches in case of exception.
fixes#1395
This patch is a rebase of a patch originally written by Brian. I didn't change any of the intent of Brian's patch, just ported it to current trunk.
refs #1363
This patch was originally written by Brian, but was re-recorded by Zooko to use
darcs replace instead of hunks for any file in which it would result in fewer
total hunks.
refs #1363
This patch was written by Brian but was re-recorded by Zooko (with David-Sarah looking on) to use darcs replace instead of editing to rename the three variables to their new names.
refs #1363
When blocks terminate (either COMPLETE or CORRUPT/DEAD/BADSEGNUM), the
_shares_from_server dict was being popped incorrectly (using shnum as the
index instead of serverid). I'm still thinking through the consequences of
this bug. It was probably benign and really hard to detect. I think it would
cause us to incorrectly believe that we're pulling too many shares from a
server, and thus prefer a different server rather than asking for a second
share from the first server. The diversity code is intended to spread out the
number of shares simultaneously being requested from each server, but with
this bug, it might be spreading out the total number of shares requested at
all, not just simultaneously. (note that SegmentFetcher is scoped to a single
segment, so the effect doesn't last very long).
No behavioral changes, just updating variable/method names and log messages.
The effects outside these three files should be minimal: some exception
messages changed (to say "server" instead of "peer"), and some internal class
names were changed. A few things still use "peer" to minimize external
changes, like UploadResults.timings["peer_selection"] and
happinessutil.merge_peers, which can be changed later.
Pass around IServer instance instead of (peerid, rref) tuple. Replace
"descriptor" with "server". Other replacements:
get_all_servers -> get_connected_servers/get_known_servers
get_servers_for_index -> get_servers_for_psi (now returns IServers)
This change still needs to be pushed further down: lots of code is now
getting the IServer and then distributing (peerid, rref) internally.
Instead, it ought to distribute the IServer internally and delay
extracting a serverid or rref until the last moment.
no_network.py was updated to retain parallelism.
* repairer (really the uploader) reads beyond end of input file (Uploadable)
* new-downloader does not tolerate overreads
* uploader does lots of tiny reads (inefficient)
This fixes the last two. The uploader still does a single overread at the end
of the input file, but now that's ok so we can leave it in place. The
uploader now expects the Uploadable to behave like a normal disk
file (reading beyond EOF will return less data than was asked for), and now
the new-downloadable behaves that way.
fixes#1191
Patch by Brian. This patch description was actually written by Zooko, but I forged Brian's name on the "author" field so that he would get credit for this patch in revision control history.
deliver all shares at once instead of feeding them out one-at-a-time.
Also fix distribution of real-number-of-segments information: now all
CommonShares (not just the ones used for the first segment) get a
correctly-sized hashtree. Previously, the late ones might not, which would
make them crash and get dropped (causing the download to fail if the initial
set were insufficient, perhaps because one of their servers went away).
Update tests, add some TODO notes, improve variable names and comments.
Improve logging: add logparents, set more appropriate levels.
This avoids spamming the "recent uploads and downloads" /status page from
FileNode instances that were created for a directory read but which nobody is
ever going to read from. I also cleaned up the way DownloadStatus instances
are made to only ever do it in the CiphertextFileNode, not in the
higher-level plaintext FileNode. Also fixed DownloadStatus handling of read
size, thanks to David-Sarah for the catch.
seems to avoid the #1155 log message which reveals the URI (and filecap).
Also add an [ERROR] marker to the flog entry, since unregisterProducer also
makes interrupted downloads appear "200 OK"; this makes it more obvious that
the download did not complete.
The lost-progress bug occurred when two simultanous read() calls fetched
different segments, and the first one failed (due to corruption, or the other
bugs in #1154): the second read() would never complete. While in this state,
cancelling the second read by having its consumer call stopProducing) would
trigger the cancel-intolerance bug. Finally, in downloader.node.Cancel,
prevent late cancels by adding an 'active' flag
The Range header causes n.read() to be called with an offset= of type 'long',
which eventually got used in a Spans/DataSpans object's __len__ method.
Apparently python doesn't permit __len__() to return longs, only ints.
Rewrote Spans/DataSpans to use s.len() instead of len(s) aka s.__len__() .
Added a test in test_download. Note that test_web didn't catch this because
it uses mock FileNodes for speed: it's probably time to rewrite that.
There is still an unresolved error-recovery problem in #1154, so I'm not
closing the ticket quite yet.
The fixed 10-second timer will eventually be replaced with a per-server
value, calculated based on observed response times.
test_hung_server.py: enhance to exercise DYHB=OVERDUE state. Split existing
mutable+immutable tests into two pieces for clarity. Reenabled several tests.
Deleted the now-obsolete "test_failover_during_stage_4".