commit 33acf1a27bbf8e5a0f4eabe051384ba0d5043600
from: Stefan Sperling <stsp@stsp.name>
via: Thomas Adam <thomas@xteddy.org>
date: Fri Oct 15 19:22:03 2021 UTC

limit delta chain length in newly created pack files to 32 deltas

Our former limit was 128 which is fairly high. Git uses 50 by default.
A smaller limit results in slightly larger pack files but makes both
packing and unpacking faster.

commit - 31f4c1e6659c2fbc73b69effcd47acca428c1c34
commit + 33acf1a27bbf8e5a0f4eabe051384ba0d5043600
blob - 1f5a114797aaf64af813a2fd8917298bfe14f048
blob + 8c74017dc075cbe01de88fbcfc91baad551447ae
--- lib/pack_create.c
+++ lib/pack_create.c
@@ -219,7 +219,7 @@ pick_deltas(struct got_pack_meta **meta, int nmeta, in
 			}
 			base = meta[j];
 			/* long chains make unpacking slow, avoid such bases */
-			if (base->nchain >= 128 ||
+			if (base->nchain >= 32 ||
 			    base->obj_type != m->obj_type)
 				continue;