I personally used "tahoe start/restart -m ../MY-TESTNET/node*" all the time,
to spin up or update a local testgrid while iterating over new code. However,
with the recent switch from "subprocess.Popen(/bin/twistd)" to "import and
call twistd.run()" in scripts/startstop_node.py (yay fewer processes!),
"start -m" broke, and fixing it requires os.fork, which is unavailable on
windows (boo windows!). And I was probably the only one using -m. So in the
interests of uniformity among platforms and simpler code (yay negative code
days!), we're just removing -m from everything. I will start using a little
shell script or something to simulate the removed functionality.
This patch also cleans up CLI-function calling a bit: get the basedir from
the config dict (instead of sometimes from a separate argument), and always
return a numeric exit code.
Specifically, test_runner.CreateNode.test_client failed, because the
os.fork-is-present test decided that --multiple should not be allowed on
windows, even though --multiple works just fine for 'tahoe create-client'.
The only restriction on --multiple is for 'tahoe start' and 'tahoe restart'.
This needs a different approach, probably by cleaning up BasedirMixin. We
should only be withholding --multiple on windows for "start" and
"restart". (we should continue withholding --multiple on all platforms for
"run").
This reverts (git) commit f3adb037ae:
"startstop_node.py: fix "tahoe start -m" by forking before non-final targets"
* don't advertise -m flag on tahoe start/restart/run unless os.fork is
available (i.e. windows)
* test_runner.py: add test to exercise "start/stop/restart -m"
* 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.
If you are investigating the bug in new-downloader, one way to investigate might be to change this ordering to a different fixed order (e.g. rotate by 4 instead of rotate by 5) and observe how the behavior of new-downloader differs in that case.
Kyle's OpenBSD buildslave used 41 reads when doing this test. The fact that I'm blindly bumping this number up to match the observed behavior probably means this isn't a good criterion to be testing for anyway. But perhaps someone else (Brian) could investigate why that run on Kyle's OpenBSD box took four more reads than we expected, and whether the fact that it took 41 reads to do this operation is indicative of an actual problem.
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.
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.
