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- Path: sparky!uunet!tis.com!mjr
- From: mjr@tis.com (Marcus J Ranum)
- Newsgroups: comp.unix.ultrix
- Subject: Re: Recommendations for high disk throughput
- Date: 28 Jan 1993 03:52:41 GMT
- Organization: Trusted Information Systems, Inc.
- Lines: 40
- Message-ID: <1k7la9INNk6c@sol.tis.com>
- References: <C1BFFz.EEr@news.iastate.edu> <1993Jan27.205507.13234@grc.genroco.com> <C1JA9I.50x@news.iastate.edu>
- NNTP-Posting-Host: sol.tis.com
-
- john@iastate.edu (John Hascall) writes in response to a posting from
- joe@grc.genroco.com (Joe Nordman)
-
- [...A discussion about some assumptions in respect to the
- paper about why SCSI is better than IPI for NFS servers...]
-
- > Not that I doubt any of what was said, but it only seems fair
- > that people know that GENROCO makes IPI controllers for DECs...
-
- None of that invalidates what Joe said, either. If I recall
- the paper, it was based on the observation that high NFS traffic
- tends to look fairly random, which defeats IPI's lookahead and
- other strategies, therefore, since SCSI disks are cheaper, they
- are better. In short: "NFS traffic is a pain no matter what, so
- using cheaper disks is a good bet" which is somewhat true, but
- doesn't take into account cases where the NFS traffic is bursty,
- consisting of clients that do a whole series of sequential reads
- or writes - in that case IPI is going to win pretty nicely.
-
- I'm not sure I'd recommend IPI as *the* way of making
- my NFS server faster. In order I'd go with asynchronous NFS
- and a UPS (UPS' on servers are a good idea anyhow) or an NVRAM
- board if I had money to burn. IPI's going to be a lot better
- for database or other applications like imaging than it will
- be for NFS. Since the original question was *NOT* about NFS,
- but was about how to make news faster, IPI is still a pretty
- decent option, not only because of the faster disks, but
- because they're nice and big, too(*). There are some amazingly
- hot RAID controllers for IPI made by CDC, which can access
- some ludicrous amount of storage in the 60Gb range. Enough
- for most news feeds unless you carry the aquaria and MUD
- groups.
-
- mjr.
-
- (*) You can also do fun still like hot-swap and dual port
- IPI disks, which you can only do with SCSI if you like
- having your bus hang, crash, and burn.
- --
- "guns don't die. people do."
-