From: Patrick Steinhardt <ps@pks.im>
Date: Thu, 29 Oct 2026 08:05:42 GMT
Subject: Re: [PATCH v2 1/4] loose: use finite timeout when locking "loose-object-idx" file
Message-ID: <auL-Ta8DTicSLW7W@pks.im>
In-Reply-To: <20261029002413.3291184-2-jltobler@gmail.com>

On Wed, Oct 28, 2026 at 07:24:10PM -0500, Justin Tobler wrote:
> Loose object index file writers first attempt to acquire a lock via
> `repo_hold_lock_file_for_update_timeout()` and specify a timeout value
> of -1. With a negative timeout value, the lock acquisition retries
> indefinitely while the lockfile still exists. If a process dies while
> holding the lock and leaves a stale lockfile behind, every subsequent
> writer of the mapping file hangs forever instead of reporting an error.
> 
> Introduce LOOSE_OBJECT_IDX_LOCK_TIMEOUT_MS to set the timeout to 1000ms
> and use it for all callers that lock a "loose-object-idx" file. A value
> of 1000ms matches the default timeout used for "core.packedRefsTimeout"
> and should provide concurrent writers sufficient time to acquire the
> lock.

Right, aborting eventually is way better compared to blocking
indefinitely. Ideally we should also make this setting configurable. But
I think it's fine to skip that for now and fix that at a later point in
time.

Patrick