carbon2-commit: Port write-region-inhibit-sync, allowing avoidance of bad FS performance.

changeset: 4531:eb82259f265d18b2bc5c9e76d0f1222f5a0976e8 parent: 4525:89406c31b12521258c83389d19f80440a3a7ce48 user: Aidan Kehoe <kehoea(a)parhasard.net&gt; date: Sat Aug 09 16:44:46 2008 +0200 files: src/ChangeLog src/fileio.c description: Port write-region-inhibit-sync, allowing avoidance of bad FS performance. See http://shaver.off.net/diary/2008/05/25/fsyncers-and-curveballs/ for more details. 2008-08-09 Aidan Kehoe <kehoea(a)parhasard.net&gt; Integrate Romain Francoise' 2005-09-14 (pre-GPLV3) GNU change, which can allow much better performace with some stupid filesystems: * fileio.c (write_region_inhibit_fsync): New variable. (Fwrite_region): Use it to skip call to fsync. (syms_of_fileio): Initialize it. diff -r 89406c31b12521258c83389d19f80440a3a7ce48 -r eb82259f265d18b2bc5c9e76d0f1222f5a0976e8 src/ChangeLog --- a/src/ChangeLog Sat Aug 09 12:13:19 2008 +0200 +++ b/src/ChangeLog Sat Aug 09 16:44:46 2008 +0200 ＠＠ -1,3 +1,12 ＠＠ 2008-08-05 Aidan Kehoe <kehoea＠parhasa +2008-08-09 Aidan Kehoe <kehoea(a)parhasard.net&gt; + + Integrate Romain Francoise' 2005-09-14 (pre-GPLV3) GNU change, + which can allow much better performace with some stupid + filesystems: + * fileio.c (write_region_inhibit_fsync): New variable. + (Fwrite_region): Use it to skip call to fsync. + (syms_of_fileio): Initialize it. + 2008-08-05 Aidan Kehoe <kehoea(a)parhasard.net&gt; * mule-charset.c (complex_vars_of_mule_charset): diff -r 89406c31b12521258c83389d19f80440a3a7ce48 -r eb82259f265d18b2bc5c9e76d0f1222f5a0976e8 src/fileio.c --- a/src/fileio.c Sat Aug 09 12:13:19 2008 +0200 +++ b/src/fileio.c Sat Aug 09 16:44:46 2008 +0200 ＠＠ -110,6 +110,11 ＠＠ int disable_auto_save_when_buffer_shrink int disable_auto_save_when_buffer_shrinks; Lisp_Object Vdirectory_sep_char; + +#ifdef HAVE_FSYNC +/* Nonzero means skip the call to fsync in Fwrite-region. */ +int write_region_inhibit_fsync; +#endif /* These variables describe handlers that have "already" had a chance to handle the current operation. ＠＠ -3568,7 +3573,7 ＠＠ here because write-region handler writer Disk full in NFS may be reported here. */ /* mib says that closing the file will try to write as fast as NFS can do it, and that means the fsync here is not crucial for autosave files. */ - if (!auto_saving && fsync (desc) < 0 + if (!auto_saving && !write_region_inhibit_fsync && fsync (desc) < 0 /* If fsync fails with EINTR, don't treat that as serious. */ && errno != EINTR) { ＠＠ -4560,6 +4565,15 ＠＠ File name in which we write a list of al */ ); Vauto_save_list_file_name = Qnil; +#ifdef HAVE_FSYNC + DEFVAR_BOOL ("write-region-inhibit-fsync", &write_region_inhibit_fsync /* +*Non-nil means don't call fsync in `write-region'. +This variable affects calls to `write-region' as well as save commands. +A non-nil value may result in data loss! +*/ ); + write_region_inhibit_fsync = 0; +#endif + DEFVAR_LISP ("auto-save-list-file-prefix", &Vauto_save_list_file_prefix /* Prefix for generating auto-save-list-file-name. Emacs's pid and the system name will be appended to _______________________________________________ XEmacs-Patches mailing list XEmacs-Patches(a)xemacs.org http://calypso.tux.org/cgi-bin/mailman/listinfo/xemacs-patches