Messages in this thread |  | | From | Matthias Urlichs <> | Subject | Re: Memory upgrade: not faster / nfs | Date | Sat, 26 Oct 1996 03:35:47 -0200 |
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In linux.dev.kernel, article <"sim0s4.fzi.178:25.10.96.16.26.14"@fzi.de>, Christoph Trautwein <trautw@fzi.de> writes: > ------- =_aaaaaaaaaa0 > Content-Type: text/plain; charset="us-ascii" > > Problem: > ! NFS is a filesystem. Filesystems are not cached. > ! The only thing that's cached in UN*X are block > ! devices. This is the wrong place to cache. > This is true for UN*X in general, I'd say, but NOT for Linux 2.0.
-rwxr-xr-x 1 smurf user 412521 Feb 21 1996 XXX.eps
work:/uneu/urlichs 1243$ time cat XXX.eps >/dev/null 0.01user 0.22system 0:02.07elapsed 11%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+0minor)pagefaults 0swaps
work:/uneu/urlichs 1244$ time cat XXX.eps >/dev/null 0.02user 0.04system 0:00.08elapsed 75%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+0minor)pagefaults 0swaps
YOU tell me how to pull 5 MBytes/sec over a 10 MBit/sec Ethernet if you don't believe me. :-)
> Is it correct how I see these things? No.
> Why are filesystems not buffered? Because initially, there were no file systems without a corresponding block device, and buffering the whole device means fewer numbers to store. Plus, the metadata on a file system obviously can't be cached in the file cache because there's no file associated with them.
> Is there a nfs implementation that does buffering? Yes. See above.
-- But we've only fondled the surface of that subject. --Virginia Masters [of Master & Johnson] -- Matthias Urlichs \ noris network GmbH / Xlink-POP Nürnberg Schleiermacherstraße 12 \ Linux+Internet / EMail: urlichs@noris.de 90491 Nürnberg (Germany) \ Consulting+Programming+Networking+etc'ing PGP: 1024/4F578875 1B 89 E2 1C 43 EA 80 44 15 D2 29 CF C6 C7 E0 DE Click <A HREF="http://info.noris.de/~smurf/finger">here</A>. 42
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