kim@uts.amdahl.com (Usenet Administration) (01/31/89)
In article <2188@van-bc.UUCP>, lphillips@lpami.wimsey.bc.ca (Larry Phillips) writes: > In <2144@vu-vlsi.Villanova.EDU>, cheung@vu-vlsi.Villanova.EDU (Wilson Cheung) writes: > > I've been hearing people getting satisfactory results with FFS using > >a 32K setting for MaxTransfer. > > The best performance is had on FFS by using no MaxTransfer entry at all. > MaxTransfer is a limiting number, and no entry for it allows the file system to > ask for as much data as it wants at a time. MaxTransfer is only required if the > driver cannot handle unlimited size data requests. That's pretty much the same conclusion I came to. I did an extensive set of "diskperfa" runs over the weekend on several partitions of varying size, fragmentation, etc. I did alot of fiddling with MaxTransfer, Buffers, and FastMemFirst along the way. Naturally, this was just before your posting came in (sigh!) ... I've attached a few of the results to this posting, as well as some random thoughts that occurred to me whilst doing these tests. There *does* seem to be a bit of a "peak" for the 80S/2090A combo at MaxTransfer = 32768, that falls off a little when it's set *larger*. Maybe some effect of the 80S's on-drive cache, of possibly a "granularity" effect of "diskperfa" itself (though the numbers were repeatable to a large degree). > >Unfortunately the driver for my hard disk will only permit a MaxTranser of 512K bytes. > > That is unfortunate. Are you sure about the 512 bytes figure? I have seen a > number of figures for different products, but none as low as this. What > driver/controller are you running? Yeah ... *very* unfortunate, if the numbers for 512 are anything like the ones below! > The only recommendation I can think of is to wait for an upgrade to the driver, > or if that will not happen, change to another controller. Runninf FFS at a > maxTransfer of 512 bytes offers only marginal improvement in speed and drive > data capacity. Almost exactly 9 times better than a floppy, but only 1/5th as the best 32k buf read performance I saw! I also included runs for vd0:, rad:, ram:, and df0: ... for comparison and "calibration" purposes. Remember ... there are lies, damn lies, and benchmarks. Your mileage WILL vary! /kim ========================================================================== Quantum-80S/2090A "diskperfa" benchmarks - 01/29/89 System: B2000 w/68010; ASDG 8MI with 6 Meg; rslclock running; 1024 FaccII buffers; 4 Meg vd0:; floppy-sized rad:; Mask = 0x007FFFFE; BufMemType = 1; Buffers = 60 except as noted. Partitions: ROOT0: 31 Meg, 63% full, minimal fragmentation ROOT1: 31 Meg, 28% full, some fragmentation [not included] ROOT2: 15 Meg, 72% full, normal fragmentation [not included] TEST: 3 Meg, 51% full, little fragmentation [not included] Conclusion: Used MaxTransfer = 32768, Buffers = 80 (40 in TEST:), with FasMemFirst. Notes: FastMemFirst seems to help writes more than reads. There's a "peaking" at about MaxTransfer = 32K ... some falloff; falloff more visible on smaller and/or more framented partitions. The "diskperfa" test *may* run a little faster at some of the large MaxTransfer's, even though the results of *disk* performance are a little slower (per Pete Jordan). Next time, time the "diskperfa" run time, dummy! The CBM MaxTransfer (whatever it is) is pretty good. VD0:'s alot slower than I thought (!). RAM:'s about 650K ... thought I'd seen it elsewhere in the 800K range. Floppy's are truly miserable!!! Had 1024 FaccII buffers, with write retention OFF for DF0:. RAD: was *not* FFS formatted ... just the OldFileSystem. Could probably "tune" the partitions better ... the above numbers seem like a good compromise though (besides, that's where "diskperf" hit it's highest "read" maximum: 512K (524,288), in a semi-repeatable fashion. People who have to set MaxTransfer down to 512 *bytes*, should raise Hell with their vendor(s)! 512 MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] File create/delete: create 13 files/sec, delete 32 files/sec Directory scan: 72 entries/sec Seek/read test: 103 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25206 byte/sec r/w speed: buf 4096 bytes, rd 100824 byte/sec, wr 27306 byte/sec r/w speed: buf 8192 bytes, rd 104857 byte/sec, wr 27306 byte/sec r/w speed: buf 32768 bytes, rd 104857 byte/sec, wr 27594 byte/sec 8K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] File create/delete: create 14 files/sec, delete 31 files/sec Directory scan: 73 entries/sec Seek/read test: 101 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25206 byte/sec r/w speed: buf 4096 bytes, rd 218453 byte/sec, wr 137970 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 174762 byte/sec r/w speed: buf 32768 bytes, rd 327680 byte/sec, wr 187245 byte/sec 16K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] w/FastMemFirst File create/delete: create 13 files/sec, delete 32 files/sec Directory scan: 73 entries/sec Seek/read test: 102 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25206 byte/sec r/w speed: buf 4096 bytes, rd 218453 byte/sec, wr 131072 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 187245 byte/sec r/w speed: buf 32768 bytes, rd 374491 byte/sec, wr 218453 byte/sec DEFAULT MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] File create/delete: create 13 files/sec, delete 32 files/sec Directory scan: 72 entries/sec Seek/read test: 100 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25206 byte/sec r/w speed: buf 4096 bytes, rd 218453 byte/sec, wr 137970 byte/sec r/w speed: buf 8192 bytes, rd 262144 byte/sec, wr 187245 byte/sec r/w speed: buf 32768 bytes, rd 436906 byte/sec, wr 238312 byte/sec 16K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] File create/delete: create 14 files/sec, delete 32 files/sec Directory scan: 73 entries/sec Seek/read test: 103 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25206 byte/sec r/w speed: buf 4096 bytes, rd 238312 byte/sec, wr 137970 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 187245 byte/sec r/w speed: buf 32768 bytes, rd 436906 byte/sec, wr 218453 byte/sec DEFAULT MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] w/FastMemFirst File create/delete: create 14 files/sec, delete 31 files/sec Directory scan: 73 entries/sec Seek/read test: 102 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25450 byte/sec r/w speed: buf 4096 bytes, rd 201649 byte/sec, wr 137970 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 187245 byte/sec r/w speed: buf 32768 bytes, rd 436906 byte/sec, wr 238312 byte/sec 24K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] w/FastMemFirst File create/delete: create 12 files/sec, delete 33 files/sec Directory scan: 74 entries/sec Seek/read test: 101 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25206 byte/sec r/w speed: buf 4096 bytes, rd 218453 byte/sec, wr 137970 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 187245 byte/sec r/w speed: buf 32768 bytes, rd 374491 byte/sec, wr 238312 byte/sec 32K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] File create/delete: create 14 files/sec, delete 33 files/sec Directory scan: 73 entries/sec Seek/read test: 101 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25450 byte/sec r/w speed: buf 4096 bytes, rd 218453 byte/sec, wr 137970 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 187245 byte/sec r/w speed: buf 32768 bytes, rd 436906 byte/sec, wr 238312 byte/sec 32K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] w/FastMemFirst File create/delete: create 13 files/sec, delete 32 files/sec Directory scan: 73 entries/sec Seek/read test: 100 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25206 byte/sec r/w speed: buf 4096 bytes, rd 218453 byte/sec, wr 137970 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 187245 byte/sec r/w speed: buf 32768 bytes, rd 524288 byte/sec, wr 238312 byte/sec 64K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] File create/delete: create 14 files/sec, delete 32 files/sec Directory scan: 75 entries/sec Seek/read test: 101 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 24966 byte/sec r/w speed: buf 4096 bytes, rd 201649 byte/sec, wr 131072 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 174762 byte/sec r/w speed: buf 32768 bytes, rd 436906 byte/sec, wr 238312 byte/sec 64K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] w/FastMemFirst File create/delete: create 14 files/sec, delete 33 files/sec Directory scan: 73 entries/sec Seek/read test: 101 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25450 byte/sec r/w speed: buf 4096 bytes, rd 218453 byte/sec, wr 137970 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 187245 byte/sec r/w speed: buf 32768 bytes, rd 436906 byte/sec, wr 238312 byte/sec 128K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] w/FastMemFirst File create/delete: create 13 files/sec, delete 32 files/sec Directory scan: 73 entries/sec Seek/read test: 104 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 24966 byte/sec r/w speed: buf 4096 bytes, rd 201649 byte/sec, wr 131072 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 174762 byte/sec r/w speed: buf 32768 bytes, rd 436906 byte/sec, wr 238312 byte/sec 128K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] File create/delete: create 14 files/sec, delete 34 files/sec Directory scan: 77 entries/sec Seek/read test: 100 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25206 byte/sec r/w speed: buf 4096 bytes, rd 218453 byte/sec, wr 124830 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 174762 byte/sec r/w speed: buf 32768 bytes, rd 436906 byte/sec, wr 238312 byte/sec 256K MaxTransfer on FF0: 31M 39869 23177 63% 0 Read/Write ROOT0 [60 Bufs] w/FastMemFirst File create/delete: create 13 files/sec, delete 31 files/sec Directory scan: 73 entries/sec Seek/read test: 100 seek/reads per second r/w speed: buf 512 bytes, rd 70849 byte/sec, wr 25206 byte/sec r/w speed: buf 4096 bytes, rd 201649 byte/sec, wr 137970 byte/sec r/w speed: buf 8192 bytes, rd 291271 byte/sec, wr 174762 byte/sec r/w speed: buf 32768 bytes, rd 436906 byte/sec, wr 238312 byte/sec VD0: 4.0M 13 8401 0% 0 Read/Write ASDG-RAM w/FastMemFirst File create/delete: create 15 files/sec, delete 35 files/sec Directory scan: 41 entries/sec Seek/read test: 106 seek/reads per second r/w speed: buf 512 bytes, rd 60963 byte/sec, wr 39125 byte/sec r/w speed: buf 4096 bytes, rd 97090 byte/sec, wr 54613 byte/sec r/w speed: buf 8192 bytes, rd 104857 byte/sec, wr 58254 byte/sec r/w speed: buf 32768 bytes, rd 113975 byte/sec, wr 60963 byte/sec RAD: 837K 2 1756 0% 0 Read/Write RAMB0 w/FastMemFirst File create/delete: create 17 files/sec, delete 38 files/sec Directory scan: 41 entries/sec Seek/read test: 110 seek/reads per second r/w speed: buf 512 bytes, rd 65536 byte/sec, wr 45990 byte/sec r/w speed: buf 4096 bytes, rd 109226 byte/sec, wr 68985 byte/sec r/w speed: buf 8192 bytes, rd 119156 byte/sec, wr 74898 byte/sec r/w speed: buf 32768 bytes, rd 131072 byte/sec, wr 77101 byte/sec RAM: 2K 6 0 100% 0 Read/Write RAM-DISK Type Available In-Use Maximum Largest fast 4030968 2777312 6808280 2097120 w/FastMemFirst File create/delete: create 4 files/sec, delete 8 files/sec Directory scan: 4 entries/sec Seek/read test: 39 seek/reads per second r/w speed: buf 512 bytes, rd 154202 byte/sec, wr 84562 byte/sec r/w speed: buf 4096 bytes, rd 436906 byte/sec, wr 137970 byte/sec r/w speed: buf 8192 bytes, rd 655360 byte/sec, wr 145635 byte/sec r/w speed: buf 32768 bytes, rd 655360 byte/sec, wr 154202 byte/sec DF0: 837K 2 1756 0% 0 Read/Write virgin [1024 FaccII bufs] File create/delete: create 0 files/sec, delete 1 files/sec Directory scan: 33 entries/sec Seek/read test: 38 seek/reads per second r/w speed: buf 512 bytes, rd 10968 byte/sec, wr 5382 byte/sec r/w speed: buf 4096 bytes, rd 11397 byte/sec, wr 5637 byte/sec r/w speed: buf 8192 bytes, rd 11447 byte/sec, wr 5577 byte/sec r/w speed: buf 32768 bytes, rd 11599 byte/sec, wr 5674 byte/sec ========================================================================== -- UUCP: kim@amdahl.amdahl.com or: {sun,decwrl,hplabs,pyramid,uunet,oliveb,ames}!amdahl!kim DDD: 408-746-8462 USPS: Amdahl Corp. M/S 249, 1250 E. Arques Av, Sunnyvale, CA 94086 BIX: kdevaughn GEnie: K.DEVAUGHN CIS: 76535,25
hpchang@rose.waterloo.edu (Hsi P. Chang) (02/01/89)
Since my Wedge HD crashed on me yesterday, I was forced to call RSI systems
and see what they can do about it. It turns out that I am basically screwed,
but this is not the point of this posting.
RSI has indicated that they didn't understand the MaxTransfer parameter, thus
the earlier setups all had a recommended MaxTransfer = 255. Now that they
realized their error, they recommend that MaxTransfer be set to 128000.
According to DiskPerf, my newly restored Wedge drive just gained over 50%
in performance rate. (I'm not too certain exactly how much improvement, but
I do know it's over 50%.)
On a side note. Can anyone recommend a HD Backup program ? (PD or Commercial)
I have PD access to SDBackup, Backer (Orange), Backup (DM), MRBackup.
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hpchang@rose.waterloo.{edu,cdn} Hsi P. Chang
hpchang@rose.uwaterloo.ca 3B Computer Science, Co-op.
uunet!watmath!rose!hpchang University of Waterloo, Ontario, Canada