On July 13, 2005 at 20:44, saf wrote: > I have some question about performance. I read the document: > http://www.mhonarc.org/release/MHonArc/snapshot/doc/guides/performance.html#pagelayout > > My question are the following: > FASTTEMPFILES: > To activate this option in mharc, can I simply add in config.sh the line: > # Uses fast temp files > > M2H_FASTTEMPFILES=1 > > Then I do "make config" and all is fine?
Note, there is a mharc-users list for discussions specific to mharc. I'll still respond since you also ask questions specific to MHonArc. For mharc, there exists mhonarc resource files for controlling the behavior of mhonarc. config.sh is a mharc-specific thing, and mhonarc has no knowledge about it. If you have followed the customization TIP mentioned in the mharc installation doc, <http://www.mhonarc.org/mharc/doc/install.html#customizations>, you would edit the file lib/default.mrc.in and add the following: <FastTempFiles> to it, and then run, make configure If you are not using the default.mrc.in tip, then you add the resource setting to lib/common.mrc.in and run 'make configure'. > Why does he create temporary files? Why will not be the file simply in > the memory in a string buffer of Perl? The data is in memory. Temporary files are mainly used for file integrity (with security as a secondary role). When mhonarc writes a file, it first writes to a temporary file, and if no I/O errors (or other error) occur, the file is renamed to the destination file. This way, the original file (if it exists, which it commonly does when editing message files and writing the database file) is left untouched if a serious error occurs, allowing for easier recovery (if required). Therefore, from a strictly I/O performance perspective after the temporary file is created, there is no loss. The rename operation is fast, and atomic, so there should be no real performance concern there. Where performance is hit is in the initial creating of the temporary file (when FASTTEMPFILES is disabled, the default). For security reasons (see FASTTEMPFILES resource page for what the security reasons are), a random filename must be created, and if File::Temp is installed, some extra security checks are done. Unfortunately, this takes time, and it is noticable if dealing with high volume. If your archive file permissions are configured in a manner where the security risks are not an issue, FASTTEMPFILES can be enabled. A simple filenaming algorithm is used avoiding the complexity of generating a random filename along with skipping any File::Temp security checks. > For the QUIET option: > How can I activate the quiet option in mharc? I don't find a line in the > "config.sh" file to specify an extra command line? The QUIET option is disabled automatically by mharc. --ewh
