Re: [PATCH v3] index-pack: retain child bases in delta cache

From: Arijit Banerjee <arijit91@gmail.com>
Date: Jun 5, 2026, 21:18 UTC
Message-ID: <08B48BBE-4084-4619-94B0-503158B93BEF@gmail.com>
In-Reply-To: <20260604071204.GA3196596@coredump.intra.peff.net>

Apologies, my earlier replies were sent through GitHub's notification emails and appeared only as PR comments, so they did not reach the mailing list.

On Thu, Jun 4, 2026, Jeff King wrote:

> So I am happy with either v2 or v3.

I also did not see a meaningful performance difference between v2 and v3. I am happy with either direction and defer to the maintainers on whether v3's more precise release is worth the added complexity.

On Wed, Jun 3, 2026, Derrick Stolee wrote:

> Did you see any evidence that this change has the intended effect of
> reducing process memory proactively instead of relying on cache evictions?

I do not have strong RSS evidence. The spot checks showed no meaningful RSS change, and max RSS is not a good signal here because free_base_data() lowers Git's internal base_cache_used accounting but may not return pages to the OS or reduce the recorded peak.

The evidence for v3 is therefore structural: it releases the cached data once all direct children have been dispatched and retain_data reaches zero, rather than waiting for cache-pressure eviction.

Thanks, Arijit