From: Junio C Hamano Date: Thu, 01 Aug 2013 18:39:32 GMT Subject: Re: [PATCH v2 1/2] sha1_file: introduce close_one_pack() to close packs on fd pressure Message-ID: <7v4nb9s1az.fsf@alter.siamese.dyndns.org> In-Reply-To: Brandon Casey writes: > I've been looking closer at uses of p->windows everywhere, and it > seems that we always open_packed_git() before we try to create new > windows. There doesn't seem to be any reason that we can't continue > to use the existing open windows even after closing the pack file. > ... > If we don't need to close_pack_windows(), find_lru_pack() doesn't > strictly need to reject packs that have windows in use. That makes me feel somewhat uneasy. Yes, you can open/mmap/close and hold onto the contents of a file still mapped in-core, and it may not count as "open filedescriptor", but do OSes allow infinite such mmapped regions to us? We do keep track of number of open windows, but is there a way for us to learn how close we are to the limit?