Hello managers,
thank you all for your responses to my question:
> i've seen some discussion here about prestoserve and advfs, but no
> statement whether it's useful or more or less senseless.
> We are thinking about to buy prestoserve for our alpha 2100 (DU 3.2C)
> with only advfs filesystems (except for / and /usr) and would like
> to know some pros and cons about that...
> Our dec support told me that this configuration should give no
> problems, but that he has no time to do performance tests...
> (shouldn't he have some docs where this is described???)
> Any (bad/good) experience/news??
The answers are included below. My personal feeling now is:
ADVFS and Prestoserve *may* work together without problems after
careful installation, but there will not be much performance gain...
Please note especially the answer of Mark Zander!
So i think we will not buy prestoserve for our 2100 with mostly
local data-disks.
Thanks!
Bernt Christandl
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- Bernt Christandl / Max Planck Institut fuer Extraterrestrische Physik -
- D-85740 Garching / Phone: +49/89/3299-3346 / Fax: +49/89/3299-3569 -
- Internet: beb_at_mpe-garching.mpg.de -
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kaiser_at_heron.enet.dec.com said:
> Bernt --
> If it's for NFS among NFS V3 systems, there's no sense buying
> Prestoserve, because the purpose it serves is built into the V3
> protocol. You should have NFS V3 from Alpha systems with UNIX, and
> from current Sun and SGI systems.
> ___Pete kaiser_at_acm.org
john_at_WPI.EDU said:
> Bernt,
> We're running with an 8Mb PCI PrestoServe on our 2 CPU 2100 4/200
> running DU 3.2c and we haven't had any problems with it. We've got a
> second SCSI controller and 18Gb if disk on the system at this time.
> We've been having some random crashes recently, but DEC thinks it is
> because our RZ28 disk holding root is below rev. But in general,
> it's nice and stable.
> John
> John F. Stoffel | john_at_wpi.edu | Kill your television. College
> Computer Center |
mark.zander_at_sheridanc.on.ca said:
We have been looking in to advfs for a while now. We will be using advfs
for mainly serving NFS clients (dos PC's). The 'testing' I have done says
advfs is miles faster than ufs via NFS or from the local machine.
When it comes to using presto, ufs benefits more than advfs. For our
faster servers ufs is even faster then advfs when presto cache is on.
I did several bench mark tests to a mfs to rule out disk performance
issues. Most of the time ufs/presto came out to being very close to mfs
speeds (which is what you would expect). Advfs was always much slower
than mfs EXCEPT when dealing with data several times larger than the
presto cache size.
Here are some of my local times. Times are in seconds and an average
time is in parens (using DEC 3000/400 turbo channel)...
Command AdvFS UFS MFS
cp /mfs/bsd . 0:00.19 0:00.10 0:00.17
0:00.28 0:00.09 0:00.11
0:00.20 0:00.10 0:00.13
(binary file size 740340 bytes) (0.223) (0.097) (0.137)
cp -R /mfs/* . 0:02.47 0:00.56 0:00.42
0:02.04 0:00.53 0:00.42
0:02.46 0:00.63 0:00.37
(2.323) (0.573) (0.403)
(1.435MB in 128 files 11 directories)
and some NFS times (using 386PC)...
Command AdvFS UFS MFS
(presto) (presto)
BW-NFS 3.2.1 0:05.99 0:03.40 0:02.40
0:05.61 0:03.51 0:03.7795
(copy c:\bsd z:\) 0:05.66 0:03.31 0:02.3353
(smartdrv, 50K/8K) (5.733) (3.406) 0:02.5200
(2.7587)
(binary file size 740340 bytes)
BW-NFS 3.2.1 0:32.97 0:15.29 0:14.58
0:34.50 0:17.32 0:15.79
(xcopy c:\win31\*.* /s) 0:36.36 0:16.86 0:13.47
(smartdrv, 50K/8K) 0:32.53 0:16.10 0:15.64
(34.09) (16.39) (14.87)
(1.435MB in 128 files 11 directories)
As you can see advfs is a consistantly slower filesystem. If it did not
have so many advantages (very quick re-boots!!) we would have moved back
to ufs months ago.
Also be warned that the presto driver has a bug in it that fouls up data
on any ufs. It won't hit you for months but then it usually takes your
server down for the count!! And it almost impossible to recover from...
I have a call in to DEC about all these problems but as they say 'we're
working on it!'
later.
P.S. haven't found any docs on performance tests for advfs. Although DEC
keeps saying how much faster the fs is.
--
Mark Zander mark.zander_at_sheridanc.on.ca
Technical Support
Sheridan College (905) 845-9430 ext. 2166
1430 Trafalger Rd (905) 815-4011 fax.
Oakville, Ont.
L6H 2L1 "...and then there was one..."8-)
ron_barrett_at_corp.Cubic.COM said:
> Bernt, I've been trying to get prestoserve to work for 3 months on
> my 2100 5/250 with 2 processors. It is finally successfully running
> without crashing and corrupting filesystems. I have done *a lot* of
> filesystem restoration trying to get this to work. I'm still not
> certain what caused prestoserve to reliably crash our system and
> corrupt our filesystems. I am now running it on a ufs filesystem
> and I'm planning on trying it again on an advfs filesystem tomorrow
> evening. I'm not sure what benchmarking I'll use, but I'll
> definitely be testing this sometime soon.
koenigse_at_umw.cube.net said:
> Hi,
> I think the use of prestoserve don't depend on the filesystem.
> Prestoserve is only useful if your Alpha is a big NFS-Server. If you
> don't export many filessystems to many workstations you don't need
> prestoserve. If you do so, it is quite useful.
> Bye Chris
Received on Fri Feb 02 1996 - 12:33:54 NZDT