Actually, it's the opposite. FICON is the only way to drive an IBM 3590 drive. ESCON is way, way too slow.
I have ESCON attached B11 (9 MB/s transfer rate). I get about 4 MB/s when controller hardware compression is used. I get about 6 MB/s when compression is turned off. They are about twice as fast as my bus and tag 3480 drives. Tom Duerbusch THD Consulting >>> "Hughes, Jim" <jim.hug...@doit.nh.gov> 6/1/2009 1:55 PM >>> I am looking at table 3 on page 10 of the 3590 Introduction and Planning Guide. It mentions two things of interest: Device Data Rate(native) and Data Transfer Rate(maximum instantaneous). Device Data Rate for the E11 is 14 MB/Sec. Data Transfer Rate depends on the channel. I guess what I am reading says the tape will move around at 14 meg/sec no matter how fast I get the data to the device. FICON for tapes is a waste of time. When would FICON for tapes be a good idea? ____________________ Jim Hughes 603-271-5586 "It is fun to do the impossible." ==>-----Original Message----- ==>From: The IBM z/VM Operating System [mailto:ib...@listserv.uark.edu] On ==>Behalf Of Tom Duerbusch ==>Sent: Monday, June 01, 2009 2:46 PM ==>To: IBMVM@LISTSERV.UARK.EDU ==>Subject: Re: Z/VM and 3590 tape speed ==> ==>You're getting confused between tape drive speed and channel speed. ==> ==>The IBM 3590 E and H drives will read/write to the tape at a rate of 14 ==>MBs. Multiple that rate by your compression rate, if you have ==>compression turned on. ==> ==>The FICON channel, can operate at 200 MB or 270 MBs (on a z/890). ==> ==>So if you had 2:1 compression, you would see a transfer of 28 MBs. ==>Uncompressed it will be 14 MBs at best. ==> ==>And that is what you are seeing. ==> ==>These are data streaming drives. You have to feed the beast. If your ==>source (disk) can't keep up with the tape drive and it's compression, you ==>will see much, much lower transfer numbers. ==> ==>Tom Duerbusch ==>THD Consulting ==> ==>>>> "Hughes, Jim" <jim.hug...@doit.nh.gov> 6/1/2009 1:08 PM >>> ==>We have Z/VM 5.4, with 4 3590's attached to the z890 using FICON Express ==>with the 2-Gbps feature. The tape controller is the A60. ==> ==> ==> ==>I am doing some tape speed tests and my results are not very good. I ==>have a pipeline(look below) that writes 65,500 byte blocks to the 3590. ==>I used the cms command TAPE MODESET ( NOCOMP/COMP to turn compression ==>off/on. ==> ==> ==> ==>I see around 14 MB/sec with compression off and 28 MB/sec with ==>compression on. ==> ==> ==> ==>The 3590 Planning manual says the 3590's should operate at 200MB/sec ==>when using FICON with the 2-Gbps feature. ==> ==> ==> ==>There maybe a problem with my pipeline or my expectations. ==> ==> ==> ==>Here is the pipeline. Any insight or suggestions are welcome. ==> ==> ==> ==>/* */ ==> ==>arg blkcnt . ==> ==>if blkcnt = "" then exit 99 ==> ==> ==> ==>numeric digits 12 ==> ==> ==> ==>"TAPE REW" ==> ==>"TAPE FSF" ==> ==>say time() ==> ==>x = time("E") ==> ==> ==> ==>"PIPE literal <------------> | >> tapetest 3590 a" ==> ==> ==> ==>"PIPE (endchar ?) ", ==> ==> "? xrange 00-ff |", /* 256 characters*/ ==> ==> " dup 256 |", ==> ==> " specs todclock 1 1-* n |", ==> ==> " join 256 |", /* 64k */ ==> ==> " dup * |", ==> ==> " specs todclock 1 1-* n |", ==> ==> " fblock 65500 00 |", ==> ==> " take " blkcnt " |", ==> ==> " cnt: count lines |", ==> ==> " tape 181 |", ==> ==> " specs 1-1 1 |", ==> ==> " join 4999 |", ==> ==> " specs todclock 1 |", ==> ==> " dateconv 1.8 todabs ISODATE timeout |", ==> ==> " specs recno 1 ", ==> ==> " substring fs . f 1 of word 2 nw ", ==> ==> " /5,000 Blocks Interval Check/ nw |", ==> ==> " console |", ==> ==> " >> tapetest 3590 a ", ==> ==> "? cnt: | var xblkcnt | specs / Blocks written =/ 1 w 1 nw |", ==> ==> " console" ==> ==> ==> ==>____________________ ==> ==>Jim Hughes ==> ==>603-271-5586 ==> ==>"It is fun to do the impossible." ==> ==>
