On June 23, 2021 1:48 PM, Ævar Arnfjörð Bjarmason wrote: >> On Mon, Jun 21, 2021 at 02:59:53AM +0200, Ævar Arnfjörð Bjarmason wrote: >>> >>> On Sun, Jun 20 2021, SZEDER Gábor wrote: >>> >>> > Splitting off from: >>> > >>> > >>> > https://public-inbox.org/git/cover-0.2-0000000000-20210607T144206Z- >>> > avarab@xxxxxxxxx/T/#me5d3176914d4268fd9f2a96fc63f4e41beb26bd6 >>> > >>> > On Tue, Jun 08, 2021 at 06:14:42PM +0200, René Scharfe wrote: >>> >> I wonder (only in a semi-curious way, though) if we can detect >>> >> off-by-one errors by adding an assertion to display_progress() >>> >> that requires the first update to have the value 0, and in >>> >> stop_progress() one that requires the previous display_progress() >>> >> call to have a value equal to the total number of work items. Not >>> >> sure it'd be worth the hassle.. >>> > >>> > I fixed and reported a number of bogus progress lines in the past, >>> > the last one during v2.31.0-rc phase, so I've looked into whether >>> > progress counters could be automatically validated in our tests, >>> > and came up with these patches a few months ago. It turned out >>> > that progress counters can be checked easily and transparently in >>> > case of progress lines that are shown in the tests, i.e. that are >>> > shown even when stderr is not a terminal or are forced with >>> > '--progress'. (In other cases it's still fairly easy but not quite >>> > transparent, as I think we need changes to the progress API; more >>> > on that later in a separate >>> > series.) >>> >>> I've also been working on some progress.[ch] patches that are mostly >>> finished, and I'm some 20 patches in at the moment. I wasn't sure >>> about whether to send an alternate 20-patch "let's do this (mostly) instead?" >>> series, hence this message. >>> >>> Much of what you're doing here becomes easier after that series, e.g. >>> your global process struct in 2/7 is something I ended up >>> implementing as part of a general feature to allow progress to be >>> driven by either display_progress() *or* the signal handler itself. >> >> It's difficult to know who should rebase onto who without seeing one >> half of the patches. > >I was sort of hoping he'd take me word for it, but here it is. Don't say I didn't warn you :) > >> I couldn't find a link to them anywhere (even if they are only >> available in your fork in a pre-polished state) despite looking, but >> my apologies if they are available and I'm just missing them. > >FWIW it's avar-szeder/progress-bar-assertions in https://github.com/avar/git.git, that repo contains various functioning and not-so- >functioning code. > >https://github.com/avar/git/tree/meta/ is my version of the crappy scripts we probably all have some version of for building my own git, >things that are uncommented in series.conf is what I build my own git from. > >> In general, I think that these patches are clear and are helpful in >> pinning down issues with the progress API (which I have made a hadnful >> of times in the past), so I would be happy to see them picked up. > >Here's all 25 patches (well, around 20 before) that I had queued up locally and fixed up a bit. > >The 01/25 is something I submitted already as https://lore.kernel.org/git/patch-1.1-cba5d88ca35-20210621T070114Z-avarab@xxxxxxxxx; >hoping to get this in incrementally. > >The 12/25 is my own version of that "global progress struct, 11/25 is the first of many bugs SZEDER missed in his :) > >18/25 is the first step of the UI I was going for, the signal handler can now drive the progress bar, so e.g. during "git gc" we show (at least >for me, on git.git), a "stalled" message just before we start the actual count of "Enumerating Objects". > >After that was in I was planning on adding config-driven support to show a "spinner" when we stalled in that way, config-driven because >you could just scrape e.g. https://github.com/sindresorhus/cli-spinners/blob/main/spinners.json >into your own config. See >https://jsfiddle.net/sindresorhus/2eLtsbey/embedded/result/ :) > >19-23/25 is my grabbing of SZEDER's patches that I'm comfortable labeling as "PATCH", I think they work, but no BUG() assertions yet. I >left out the GIT_TEST_CHECK_PROGRESS parts, since my earlier works set things up to do any BUG() we trust by default. > >22/25 is what I think we should do instead of SZEDER's 6/7 >(http://lore.kernel.org/git/20210620200303.2328957-7-szeder.dev@xxxxxxxxx) >I don't think this "our total doesn't match at the end" is something we should always BUG() on, for reasons explained there. > >I am sympathetic to doing it by default though, hence the >stop_progress_early() API, that's there to allow select callers to bypass his BUG(...) assertion. > >24/25 and 25/25 are "RFC" and a rebased+modified version of SZEDER's >BUG(...) assertions. > >His series passes the test suite, but actually severely break things things. It'll make e.g. "git commit-graph write" BUG(...) out. The reason >the tests don't catch it is because we have a blind spot in the tests. > >Namely, that most things that use the progress bar API use isatty() to check if they should start_progress(). If you run the tests as e.g. >(better ways to do this, especially in parallel, most welcome): > > for t in t[0-9]*.sh; do if ! ./$t -vixd; then echo $t bad; break; fi; done > >You can discover various things that his series BUG()'s on, I fixed a couple of those myself, it's an early part of this series. > >But we'll still have various untested for BUG()'s even then, this is because you *also* have to have the test actually emit a "naked" >progress bar on stderr, if the test itself e.g. pipes fd 2 to a file it won't work. > >I created a shitty-and-mostly-broken throwaway change to search-replace all the guards of "start_progress(...)" to run unconditionally, and >convert all the "delayed" to the non-delayed version. That'll find even more BUG()'s where SZEDER's series still needs to be fixed (and also >some unrelated segfaults, I gave up on it soon after). > >Even if we fix that I wouldn't trust it, because a lot of the progress bars we have depend on the size and shape of the data we're >processing, e.g. the bug I fixed in 11/25. If people find this BUG() approach worth pursuing I think it would be better to make it an opt-in >flag we convert one caller at a time to. > >For some it's really clear that we could assert it, for others such as the commit-graph it's much more subtle, we're in some callback after >setting a "total", that callback does a "break", "continue" etc. in various places, all depending on repository data. > >It's not easy to reason about that and be certain that we can hold to the estimate. If we get it wrong someone's repo in the wild won't fully >GC because of the overly eager BUG(). > >If SZEDER wants to pursue it I think it'll be easier on top of this series, but personally I really don't see the point of spending effort on it. > >We should really be going in the other direction, of having more fuzzy ETAs, not less. > >E.g. we often have enough data at the start of "Enumerating Objects" >to give a good-enough target value, that it's 5-10% off isn't really the point, but that the user looking at it sees something better than a >dumb count-up, and can instead see that they'll probably be looking at it for about a minute. Now our API is to give no ETA/target if we're >not 100% sure, it's not good UX. > >So trying to get the current exact count/exact percentage right seems like a distraction to me in the longer term. If anything we should >just be rounding those numbers, showing fuzzy ETAs instead of percentages if we can etc. > >SZEDER Gábor (4): > commit-graph: fix bogus counter in "Scanning merged commits" progress > line > entry: show finer-grained counter in "Filtering content" progress line > progress: assert last update in stop_progress() > progress: assert counting upwards in display() > >Ævar Arnfjörð Bjarmason (21): > progress.c tests: fix breakage with COLUMNS != 80 > progress.c tests: make start/stop verbs on stdin > progress.c tests: test some invalid usage > progress.c tests: add a "signal" verb > progress.c: move signal handler functions lower > progress.c: call progress_interval() from progress_test_force_update() > progress.c: stop eagerly fflush(stderr) when not a terminal > progress.c: add temporary variable from progress struct > midx perf: add a perf test for multi-pack-index > progress.c: remove the "sparse" mode nano-optimization > pack-bitmap-write.c: add a missing stop_progress() > progress.c: add & assert a "global_progress" variable > progress.[ch]: move the "struct progress" to the header > progress.[ch]: move test-only code away from "extern" variables > progress.c: pass "is done?" (again) to display() > progress.[ch]: convert "title" to "struct strbuf" > progress.c: refactor display() for less confusion, and fix bug > progress.c: emit progress on first signal, show "stalled" > midx: don't provide a total for QSORT() progress > progress.c: add a stop_progress_early() function > entry: deal with unexpected "Filtering content" total > > cache.h | 1 - > commit-graph.c | 2 +- > csum-file.h | 2 - > entry.c | 12 +- > midx.c | 25 +- > pack-bitmap-write.c | 1 + > pack.h | 1 - > parallel-checkout.h | 1 - > progress.c | 391 ++++++++++++++++++------------- > progress.h | 50 +++- > reachable.h | 1 - > t/helper/test-progress.c | 54 +++-- > t/perf/p5319-multi-pack-index.sh | 21 ++ > t/t0500-progress-display.sh | 247 ++++++++++++++----- > 14 files changed, 537 insertions(+), 272 deletions(-) create mode 100755 t/perf/p5319-multi-pack-index.sh Is there provision for disabling progress on a per-command basis? My use case is specifically in a CI/CD script, being able to suppress progress handling. The current Jenkins plugin does not appear to have provision for hooking into a mechanism, which makes things get a bit wonky when a job runs with a pseudo-tty (as provided by Jenkins through SSH/RMI). -Randall
