Re: [PATCH v2 3/3] index-pack: eliminate unlimited recursion in get_delta_base()

On Tue, Jan 10, 2012 at 8:03 PM, Nguyen Thai Ngoc Duy <pclouds@gmail.com> wrote:

I wrote about core.deltabasecachelimit, then deleted it, thinking it should be ok, but how do handle the case when you use up cache limit? Some handled objects may be freed when we're short on cache and need to be resolved again before we could resolve an unhandled object.

Assume we're at the limit, have resolved A, which has two children B and C. When we resolve B we need to free A to keep it fit in cache. By the time we look at C, A needs to be resolved again. Without tracing back (i.e. what get_base_data() does), we don't know what we need to re-resolve among all handled objects.