# Re: [PATCH v5 03/15] index-helper: new daemon for caching index and related stuff 3 messages from 2016-04-20 to 2016-04-20. Participants: Duy Nguyen, David Turner, Johannes Schindelin. Thread: https://gitlist.dev/t/42081 ## Duy Nguyen, 2016-04-20 00:31 Subject: Re: [PATCH v5 03/15] index-helper: new daemon for caching index and related stuff Message-ID: URL: https://gitlist.dev/e/CACsJy8D_4KFjz6HefvzmWw-6Qqg0uguq8MXL6kLY0oMyVhPS0w%40mail.gmail.com ``` On Wed, Apr 20, 2016 at 6:27 AM, David Turner wrote: > Shared memory is done by storing files in a per-repository temporary > directory. This is more portable than shm (which requires > posix-realtime and has various quirks on OS X). It might even work on > Windows, although this has not been tested. There's another option, but I'm not sure if it's too clever/tricky to do. Anyway, on *nix we can send file descriptors over unix socket [2], then mmap them back to access content. On Windows, it looks like DuplicateHandle [1] can do nearly the same thing. This keeps everything in memory and we don't have to worry about cleaning up shm-* files. [1] http://lackingrhoticity.blogspot.com/2015/05/passing-fds-handles-between-processes.html [2] http://www.normalesup.org/~george/comp/libancillary/ -- Duy ``` ## David Turner, 2016-04-20 00:44 Subject: Re: [PATCH v5 03/15] index-helper: new daemon for caching index and related stuff Message-ID: <1461113092.5540.147.camel@twopensource.com> URL: https://gitlist.dev/e/1461113092.5540.147.camel%40twopensource.com In-Reply-To: ``` On Wed, 2016-04-20 at 07:31 +0700, Duy Nguyen wrote: > On Wed, Apr 20, 2016 at 6:27 AM, David Turner < > dturner@twopensource.com> wrote: > > Shared memory is done by storing files in a per-repository > > temporary > > directory. This is more portable than shm (which requires > > posix-realtime and has various quirks on OS X). It might even work > > on > > Windows, although this has not been tested. > > There's another option, but I'm not sure if it's too clever/tricky to > do. Anyway, on *nix we can send file descriptors over unix socket > [2], > then mmap them back to access content. On Windows, it looks like > DuplicateHandle [1] can do nearly the same thing. This keeps > everything in memory and we don't have to worry about cleaning up > shm-* files. > > [1] http://lackingrhoticity.blogspot.com/2015/05/passing-fds-handles- > between-processes.html > [2] http://www.normalesup.org/~george/comp/libancillary/ It's possibly a bit simpler for the index, although more complex overall since we still need to write temp files for the watchman data. Will consider/try. ``` ## Johannes Schindelin, 2016-04-20 12:19 Subject: Re: [PATCH v5 03/15] index-helper: new daemon for caching index and related stuff Message-ID: URL: https://gitlist.dev/e/alpine.DEB.2.20.1604201418550.2826%40virtualbox In-Reply-To: ``` Hi Duy, On Wed, 20 Apr 2016, Duy Nguyen wrote: > On Wed, Apr 20, 2016 at 6:27 AM, David Turner wrote: > > Shared memory is done by storing files in a per-repository temporary > > directory. This is more portable than shm (which requires > > posix-realtime and has various quirks on OS X). It might even work on > > Windows, although this has not been tested. > > There's another option, but I'm not sure if it's too clever/tricky to > do. Anyway, on *nix we can send file descriptors over unix socket [2], > then mmap them back to access content. This sounds too clever to me ;-) Ciao, Dscho ```