Messages in this thread | ![/](/images/icornerl.gif) | | Date | Sat, 04 Jan 2003 13:10:02 +0000 | From | "A.D.F." <> | Subject | Re: TCP Zero Copy for mmapped files |
| |
"J.A. Magallon" wrote: > > On 2003.01.04 A.D.F. wrote: > > FreeBSD 5.0 should already have a zero copy for mmapped files and > > IMHO it would be worth to have it in Linux 2.6 too. > > > > It would also be very nice to be able to enable zero copy for mmapped files > > by a config option. > > > > Many applications use mapped memory to serve lots of small and > > medium sized files (4 - 1024 KB) or even a few big files > > (think at web servers, i.e. Apache 2, etc.); this is done to better > > serve multiple / parallel downloads being done on the same files. > > > > Apache2 uses mmap() to open files ??
No, you cannot use mmap() to open files ... :-), at most mmap() helps caching static file contents in order to avoid too many open() / close() calls (which maybe slow).
Apache 2 seems to use sendfile (in blocking mode) by default, it uses mmap() only if you enable it (see also mod_file_cache).
Other web servers (i.e. Zeus) use widely mmap() for specific file sizes, when it is usually a strong win (specially under *BSD and Solaris) in big / busy servers with lots of RAM.
> So then there is a reason to include it in my patchset...
Certainly yes (after required bug fixes :-)
-- Nick Name: A.D.F. E-Mail: adefacc@tin.it E-Mail-Font: Courier New (plain text, no html) -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| ![\](/images/icornerr.gif) |