Re: [PATCH] change the unpack limit threshold to a saner value

Nicolas Pitre [off-list ref] writes:

Let's assume the average object size is x. Given n objects, the needed 
storage size is n*(x + b), where b is the average wasted block size on 
disk.
...
This is why I think the current default treshold should be 3 instead of 
the insane value of 5000.  But since it feels a bit odd to go from 5000 
to 3 I setled on 10.

I see you are optimizing for disk footprint, and this will
result in tons of tiny packs left between "repack -a".

I have not benched it yet, but the runtime pack handling code
was written assuming we have only a handful of big packs; I
suspect this change would affect the performance at runtime in
quite a bad way.

On Wed, 6 Dec 2006, Junio C Hamano wrote:

Nicolas Pitre [off-list ref] writes:

quoted

Let's assume the average object size is x. Given n objects, the needed 
storage size is n*(x + b), where b is the average wasted block size on 
disk.
...
This is why I think the current default treshold should be 3 instead of 
the insane value of 5000.  But since it feels a bit odd to go from 5000 
to 3 I setled on 10.

I see you are optimizing for disk footprint, and this will
result in tons of tiny packs left between "repack -a".

Depends how often i.e. how big pushes are, and how often you repack.

I have not benched it yet, but the runtime pack handling code
was written assuming we have only a handful of big packs; I
suspect this change would affect the performance at runtime in
quite a bad way.

Possibly.

Still a treshold of 5000 is way too large IMHO.