Mailing-List: contact cygwin-developers-help AT sourceware DOT cygnus DOT com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-developers-owner AT sourceware DOT cygnus DOT com Delivered-To: mailing list cygwin-developers AT sourceware DOT cygnus DOT com Message-ID: <38D0DA7B.3E46184F@vinschen.de> Date: Thu, 16 Mar 2000 13:58:35 +0100 From: Corinna Vinschen Reply-To: cygdev X-Mailer: Mozilla 4.72 [en] (Windows NT 5.0; U) X-Accept-Language: de,en MIME-Version: 1.0 To: cygdev CC: Egor Duda Subject: Re: Cygwin performance (was [ANN] PW32 the...) References: <19940315002847 DOT 279871F1B AT sabami DOT seaslug DOT org> <0457 DOT 000315 AT logos-m DOT ru> <38CF6031 DOT 7D7A28BB AT vinschen DOT de> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Corinna Vinschen wrote: > [...] > I'm absolutely sure to get a speed up by the following, without > the need of another stat-function: > > The current implementation of fhandler_disk_file::fstat() calls > three different functions which each opens the file independently: > get_file_owner(), get_file_group(), get_file_attribute(). I've > already planned to eliminate the first two functions. Instead, > the complete functionality should be offered by get_file_attribute(). > This makes sense, because get_file_attribute already knows user > and group. I hope to increase speed noticable that way. I would like to announce that I could speed up stat() already by 20-30% on remote drives and around 50% on local drives. I have done this by the aforementioned patch and additionally by calling the function `set_process_priviliges()' only once per process in dcrt0.cc instead of calling it each time, a file is opened. Actually this second change was a breakthru. Further, the call to `num_entries()' in `stat_worker ()' is only be done if the drive is no remote drive in which case the st_nlink member of the stat struct is fixed set to 2. Chris, if you like to see it, I would check it in. I have send it to cygwin-patches already. There's an additional bugfix which is described in detail in that mail. Personally, I will check out another way that could perhaps result in another 20-50% speed up but this is a bigger (say: unsafe) change in fhandler.cc and security.cc. Corinna