Re: git repack on shallow clone of large repo (linux kernel) hangs at "Enumerating objects"

[Bagas Sanjaya <bagasdotme@gmail.com>]

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Hi Jeff,

> You could try using strace or gdb to see what it's doing.
> 
> But as a guess, one thing that sometimes causes a stall near the end of
> "enumerating objects" is loosening unreachable objects that are
> currently packed. You told repack to use "-A", which asks to loosen
> those objects so they aren't lost when the old packs are deleted (as
> opposed to "-a").
> 

I attached two strace logs, one for "git repack -A -d" and one for "git
repack -a -d".

For the former, I got following excerpt before I had to SIGINT the process:

> stat("/opt/git/libexec/git-core/git", {st_mode=S_IFREG|0755, st_size=22096480, ...}) = 0
> pipe([5, 7])                            = 0
> openat(AT_FDCWD, "/dev/null", O_RDWR|O_CLOEXEC) = 8
> fcntl(8, F_GETFD)                       = 0x1 (flags FD_CLOEXEC)
> fcntl(8, F_SETFD, FD_CLOEXEC)           = 0
> rt_sigprocmask(SIG_SETMASK, ~[RTMIN RT_1], [], 8) = 0
> clone(child_stack=NULL, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7feb5ecbfa10) = 13691
> rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
> close(7)                                = 0
> read(5, "", 8)                          = 0
> close(5)                                = 0
> close(8)                                = 0
> close(4)                                = 0
> fcntl(3, F_GETFL)                       = 0 (flags O_RDONLY)
> fstat(3, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
> read(3, 0x55a540de5250, 4096)           = ? ERESTARTSYS (To be restarted if SA_RESTART is set)

I thought that in the case of "git repack -A -d", it is stucked at the
last read() before I ctrl-c'ed to trigger SIGINT.

> You'd probably want to at least say "--unpack-unreachable=some.time" to
> avoid writing out ones which are not even recent (and which is what "git
> gc" will do under the hood).
>> But if you don't care about keeping them at all (e.g., because this is
> not an active repository where other simultaneous operations may be
> taking place, so you know it is safe to delete even recent ones), then
> just "git repack -a -d" is probably your best bet.
> 
> -Peff
> 
Using "-a" instead of "-A" on git repack works. Thanks.

-- 
An old man doll... just what I always wanted! - Clara

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