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Conference aosg::lsm

Title:LSM
Moderator:SMURF::SHIDERLY
Created:Mon Jan 17 1994
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:803
Total number of notes:2852

774.0. "Poor I/O performance. Help " by HYDRA::LNARAYAN () Wed Mar 26 1997 19:16

    Hello
    
    Here is a customer benchmark suituation, which may need your
    attention/help! The application uses MFCOBOL/UNIKIX (tp monitor)
    a financial application doing batch processing ( sequential
    read/write ) The database is striped across 9 mirrored LSM volumes
    of 18 disks. And two other striped LSM volumes with other data.
    
    The I/O performance seems to be very slow. There are 8 cpus of which
    7 are idle and the active ones spends 50% user time, 49% on wait
    and the remaining 1% system time.
    
    There is no paging/swaping activity and the iostat says that it doing
    I/O at an average of about 100 kbps on each disk. I guess that the
    cpu wait is for disk I/O? Can someone help us?
    
    Thanks In Advance 
    Lakshminarayan
    
    Config
    
    DEC 8400 5/440 with 4 GB memory, 8 SCSI controller with 36 disk(RZ28M)
    distributed on it.
    Digital UNIX V4.0, LSM V4.0, MF-COBOL V3.2A
    
    The output of the commands voldis list, volprint -Avht, volprint -Apl, 
    volprint -Avl are given below
    
     voldis list
    
DEVICE       TYPE      DISK         GROUP        STATUS
rz10c        simple    rz10c        rootdg       online
rz11c        simple    rz11c        rootdg       online
rz12c        simple    rz12c        rootdg       online
rz13c        simple    rz13c        rootdg       online
rz14c        simple    rz14c        rootdg       online
rz18c        simple    rz18c        rootdg       online
rz19c        simple    rz19c        rootdg       online
rz20c        simple    rz20c        rootdg       online
rz21c        simple    rz21c        rootdg       online
rz22c        simple    rz22c        rootdg       online
rz2c         simple    rz2c         rootdg       online
rz34c        simple    rz34c        rootdg       online
rz35c        simple    rz35c        rootdg       online
rz36c        simple    rz36c        rootdg       online
rz37c        simple    rz37c        rootdg       online
rz38c        simple    rz38c        rootdg       online
rz3c         simple    rz3c         rootdg       online
rz41c        simple    rz41c        rootdg       online
rz42c        simple    rz42c        rootdg       online
rz43c        simple    rz43c        rootdg       online
rz44c        simple    rz44c        rootdg       online
rz45c        simple    rz45c        rootdg       online
rz46c        simple    rz46c        rootdg       online
rz49c        simple    rz49c        rootdg       online
rz4c         simple    rz4c         rootdg       online
rz50c        simple    rz50c        rootdg       online
rz51c        simple    rz51c        rootdg       online
rz52c        simple    rz52c        rootdg       online
rz53c        simple    rz53c        rootdg       online
rz54c        simple    rz54c        rootdg       online
rz5c         simple    rz5c         rootdg       online
rz6c         simple    rz6c         rootdg       online
    
    volprint -Avht
    
Disk group: rootdg

V  NAME         USETYPE      KSTATE   STATE    LENGTH   READPOL  PREFPLEX
PL NAME         VOLUME       KSTATE   STATE    LENGTH   LAYOUT   ST-WIDTH MODE
SD NAME         PLEX         PLOFFS   DISKOFFS LENGTH   DISK-NAME    DEVICE
                 
v  g2_vol1      fsgen        ENABLED  ACTIVE   4109440  SELECT   -
pl g2_vol1-01   g2_vol1      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz2c-01      g2_vol1-01   0        0        4109440  rz2c         rz2c
pl g2_vol1-02   g2_vol1      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz10c-01     g2_vol1-02   0        0        4109440  rz10c        rz10c

v  g2_vol2      fsgen        ENABLED  ACTIVE   4109440  SELECT   -
pl g2_vol2-01   g2_vol2      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz3c-01      g2_vol2-01   0        0        4109440  rz3c         rz3c
pl g2_vol2-02   g2_vol2      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz11c-01     g2_vol2-02   0        0        4109440  rz11c        rz11c

v  g2_vol3      fsgen        ENABLED  ACTIVE   4109440  SELECT   -
pl g2_vol3-01   g2_vol3      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz4c-01      g2_vol3-01   0        0        4109440  rz4c         rz4c
pl g2_vol3-02   g2_vol3      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz12c-01     g2_vol3-02   0        0        4109440  rz12c        rz12c

v  g2_vol4      fsgen        ENABLED  ACTIVE   4109440  SELECT   -
pl g2_vol4-01   g2_vol4      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz18c-01     g2_vol4-01   0        0        4109440  rz18c        rz18c
pl g2_vol4-02   g2_vol4      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz34c-01     g2_vol4-02   0        0        4109440  rz34c        rz34c

v  g2_vol5      fsgen        ENABLED  ACTIVE   4109440  SELECT   -
pl g2_vol5-01   g2_vol5      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz19c-01     g2_vol5-01   0        0        4109440  rz19c        rz19c
pl g2_vol5-02   g2_vol5      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz35c-01     g2_vol5-02   0        0        4109440  rz35c        rz35c

v  g2_vol6      fsgen        ENABLED  ACTIVE   4109440  SELECT   -
pl g2_vol6-01   g2_vol6      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz41c-01     g2_vol6-01   0        0        4109440  rz41c        rz41c
pl g2_vol6-02   g2_vol6      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz49c-01     g2_vol6-02   0        0        4109440  rz49c        rz49c

v  g2_vol7      fsgen        ENABLED  ACTIVE   4109440  SELECT   -
pl g2_vol7-01   g2_vol7      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz42c-01     g2_vol7-01   0        0        4109440  rz42c        rz42c
pl g2_vol7-02   g2_vol7      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz50c-01     g2_vol7-02   0        0        4109440  rz50c        rz50c

v  g2_vol8      fsgen        ENABLED  ACTIVE   4109440  SELECT   -
pl g2_vol8-01   g2_vol8      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz43c-01     g2_vol8-01   0        0        4109440  rz43c        rz43c
pl g2_vol8-02   g2_vol8      ENABLED  ACTIVE   4109440  CONCAT   -        RW
sd rz51c-01     g2_vol8-02   0        0        4109440  rz51c        rz51c

v  g3_vol       fsgen        ENABLED  ACTIVE   16437760 ROUND    -
pl g3_mir       g3_vol       ENABLED  ACTIVE   16437760 STRIPE   128      RW
sd rz5c-01      g3_mir       0        0        4109440  rz5c         rz5c
sd rz13c-01     g3_mir       4109440  0        4109440  rz13c        rz13c
sd rz21c-01     g3_mir       8218880  0        4109440  rz21c        rz21c
sd rz37c-01     g3_mir       12328320 0        4109440  rz37c        rz37c
pl g3_plex      g3_vol       ENABLED  ACTIVE   16437760 STRIPE   128      RW
sd rz20c-01     g3_plex      0        0        4109440  rz20c        rz20c
sd rz36c-01     g3_plex      4109440  0        4109440  rz36c        rz36c
sd rz44c-01     g3_plex      8218880  0        4109440  rz44c        rz44c
sd rz52c-01     g3_plex      12328320 0        4109440  rz52c        rz52c

v  g4_vol       fsgen        ENABLED  ACTIVE   16437760 ROUND    -
pl g4_plex      g4_vol       ENABLED  ACTIVE   16437760 STRIPE   128      RW
sd rz45c-01     g4_plex      0        0        4109440  rz45c        rz45c
sd rz53c-01     g4_plex      4109440  0        4109440  rz53c        rz53c
sd rz6c-01      g4_plex      8218880  0        4109440  rz6c         rz6c
sd rz14c-01     g4_plex      12328320 0        4109440  rz14c        rz14c

v  g5_vol       fsgen        ENABLED  ACTIVE   16437760 ROUND    -
pl g5_plex      g5_vol       ENABLED  ACTIVE   16437760 STRIPE   128      RW
sd rz22c-01     g5_plex      0        0        4109440  rz22c        rz22c
sd rz38c-01     g5_plex      4109440  0        4109440  rz38c        rz38c
sd rz46c-01     g5_plex      8218880  0        4109440  rz46c        rz46c
sd rz54c-01     g5_plex      12328320 0        4109440  rz54c        rz54c
    
    volprint -Apl
    
Disk group: rootdg

Plex:     g2_vol1-01
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol1 sd=rz2c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol1-01

Plex:     g2_vol1-02
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol1 sd=rz10c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol1-02

Plex:     g2_vol2-01
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol2 sd=rz3c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol2-01

Plex:     g2_vol2-02
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol2 sd=rz11c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol2-02

Plex:     g2_vol3-01
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol3 sd=rz4c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol3-01

Plex:     g2_vol3-02
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol3 sd=rz12c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol3-02

Plex:     g2_vol4-01
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol4 sd=rz18c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol4-01

Plex:     g2_vol4-02
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol4 sd=rz34c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol4-02

Plex:     g2_vol5-01
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol5 sd=rz19c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol5-01

Plex:     g2_vol5-02
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol5 sd=rz35c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol5-02

Plex:     g2_vol6-01
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol6 sd=rz41c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol6-01

Plex:     g2_vol6-02
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol6 sd=rz49c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol6-02

Plex:     g2_vol7-01
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol7 sd=rz42c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol7-01

Plex:     g2_vol7-02
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol7 sd=rz50c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol7-02

Plex:     g2_vol8-01
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol8 sd=rz43c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol8-01

Plex:     g2_vol8-02
info:     len=4109440
type:     layout=CONCAT
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g2_vol8 sd=rz51c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g2_vol8-02

Plex:     g3_mir
info:     len=16437760
type:     layout=STRIPE width=128
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g3_vol sd=rz5c-01,rz13c-01,rz21c-01,rz37c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g3_mir

Plex:     g3_plex
info:     len=16437760
type:     layout=STRIPE width=128
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g3_vol sd=rz20c-01,rz36c-01,rz44c-01,rz52c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g3_plex

Plex:     g4_plex
info:     len=16437760
type:     layout=STRIPE width=128
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g4_vol sd=rz45c-01,rz53c-01,rz6c-01,rz14c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g4_plex

Plex:     g5_plex
info:     len=16437760
type:     layout=STRIPE width=128
state:    state=ACTIVE kernel=ENABLED io=read-write
assoc:    vol=g5_vol sd=rz22c-01,rz38c-01,rz46c-01,rz54c-01
flags:    closed complete
device:   dev=42/42 path=/dev/plex/rootdg/g5_plex

    
    volprint -Avl
    
Disk group: rootdg

Volume:   g2_vol1
info:     len=4109440
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g2_vol1-01,g2_vol1-02
policies: read=SELECT (round-robin) exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=5 bdev=40/5 cdev=40/5 path=/dev/vol/rootdg/g2_vol1
perms:    user=root group=system mode=0600

Volume:   g2_vol2
info:     len=4109440
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g2_vol2-01,g2_vol2-02
policies: read=SELECT (round-robin) exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=6 bdev=40/6 cdev=40/6 path=/dev/vol/rootdg/g2_vol2
perms:    user=root group=system mode=0600

Volume:   g2_vol3
info:     len=4109440
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g2_vol3-01,g2_vol3-02
policies: read=SELECT (round-robin) exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=7 bdev=40/7 cdev=40/7 path=/dev/vol/rootdg/g2_vol3
perms:    user=root group=system mode=0600

Volume:   g2_vol4
info:     len=4109440
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g2_vol4-01,g2_vol4-02
policies: read=SELECT (round-robin) exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=8 bdev=40/8 cdev=40/8 path=/dev/vol/rootdg/g2_vol4
perms:    user=root group=system mode=0600

Volume:   g2_vol5
info:     len=4109440
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g2_vol5-01,g2_vol5-02
policies: read=SELECT (round-robin) exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=9 bdev=40/9 cdev=40/9 path=/dev/vol/rootdg/g2_vol5
perms:    user=root group=system mode=0600

Volume:   g2_vol6
info:     len=4109440
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g2_vol6-01,g2_vol6-02
policies: read=SELECT (round-robin) exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=10 bdev=40/10 cdev=40/10 path=/dev/vol/rootdg/g2_vol6
perms:    user=root group=system mode=0600

Volume:   g2_vol7
info:     len=4109440
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g2_vol7-01,g2_vol7-02
policies: read=SELECT (round-robin) exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=11 bdev=40/11 cdev=40/11 path=/dev/vol/rootdg/g2_vol7
perms:    user=root group=system mode=0600

Volume:   g2_vol8
info:     len=4109440
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g2_vol8-01,g2_vol8-02
policies: read=SELECT (round-robin) exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=12 bdev=40/12 cdev=40/12 path=/dev/vol/rootdg/g2_vol8
perms:    user=root group=system mode=0600

Volume:   g3_vol
info:     len=16437760
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g3_mir,g3_plex
policies: read=ROUND exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=13 bdev=40/13 cdev=40/13 path=/dev/vol/rootdg/g3_vol
perms:    user=root group=system mode=0600

Volume:   g4_vol
info:     len=16437760
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g4_plex
policies: read=ROUND exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=14 bdev=40/14 cdev=40/14 path=/dev/vol/rootdg/g4_vol
perms:    user=root group=system mode=0600

Volume:   g5_vol
info:     len=16437760
type:     usetype=fsgen
state:    state=ACTIVE kernel=ENABLED
assoc:    plexes=g5_plex
policies: read=ROUND exceptions=GEN_DET_SPARSE
flags:    open writeback
logging:  type=BLKNO loglen=1 serial=0/0 (disabled)
device:   minor=15 bdev=40/15 cdev=40/15 path=/dev/vol/rootdg/g5_vol
perms:    user=root group=system mode=0600

    
T.RTitleUserPersonal
Name
DateLines
774.1please run performanc monitoring toolsNETRIX::"[email protected]"Tue Apr 01 1997 11:1212
Hi,

Could you try running the volstat and monitor tools while your
benchmark is running? The monitor tool is available from
ftp://ftp.digital.com/pub/DEC/. For volstat, please post the interval
time you use and the number of operations and blocks per interval per
volume. For monitor, please post the kps, tps, and queue length per
disk.

Thanks.

[Posted by WWW Notes gateway]
774.2KITCHE::schottEric R. Schott USG Product ManagementTue Apr 01 1997 21:215
You might also try collect

see http://www-unix.zk3.dec.com/tuning/tools/tools.html


774.3Thanks for the inputs, ...HYDRA::LNARAYANTue Apr 08 1997 11:2610
    Hi
    
    Thank You for the inputs. We found that after seleting delayed writes
    with non-synchronous write, the benchmark results we interesting and
    encouraging. Now the timings are good. But I have another question.
    I have posted the question in the ASK_SSAG, Now I'll post it here as a
    reply.
    
    Thank YOu
    Lakshminarayan 
774.4performance differenceHYDRA::LNARAYANTue Apr 08 1997 11:2996
        <<< SSAG::DISK$ARCH2:[NOTES$LIBRARY.SSAG]ASK_SSAG.NOTE;32767 >>>
                    -< Ask the Storage Architecture Group >-
================================================================================
Note 6543.0           help! identify performance difference           No replies
HYDRA::LNARAYAN                                      89 lines   2-APR-1997 15:49
--------------------------------------------------------------------------------
A recent benchmark results show some strange behavior. 
This is a MF-COBOL application with unikix
(CICS for UNIX) a sequential read/write application.
We found the same application/program (with similar set of data)
that took 8 minutes on the the volumes 6,7 & 8, whereas it took 
23 minutes on the volumes 1,2,3.
This process is a part of the benchmark, which uncompresses and untar's 
8 files on eight volumes ( all are similar )  

The volumes are shown below.
My question is Why is the difference? can some one help me identify
this?

Thanks In Advance
Nari

Config:
S/W
Digital UNIX V4.0
LSM v4.0
MF COBOL 3.2A
swap 4 gb
console firmware revision 4.0

H/W
System       Alphaserver 8400 5/440
memory       4 GB

When I issue show config on the console, it lists me
on C0 four controller isp0 to isp3
and on C1 four controller kzpsa0 to kzpsa3. I dont know the
characteristics of these isp's, it came with the system as
default I guess.
the following is the SCSI device configuration

     |     isp0               BA350
     |-----------------------------------------------------
     |      |      |      |      |      |      |
 P   |    rz28  rz28m  rz28m   rz28   rz28   rz28
     |    rz1   rz2    rz3     rz4    rz5    rz6 
     |     isp1               BA356
     |-----------------------------------------------------
 C   |      |      |      |      |      |      |
     |    rz28   rz28   rz28   rz28   rz28   rz28
     |    rz9    rz10   zr11   rz12   rz13   rz14
     |     isp2               BA356
 I   |-----------------------------------------------------
     |      |      |      |      |      |      |
     |   st3255 st3255 st3255 st3255 st3255 st3255    ----> all are ST3255OW 
     |   rz17   rz18   rz19   rz20   rz21   rz22
     |     isp3               
 B   |------------------------------------------------------
     |      |
     |   rrd43
     |   rz29
 U   |            kzpsa0        BA350
     |------------------------------------------------------
     |      |      |      |      |      |      |
 S   |    rz28   rz28   rz28   rz28   rz28m  rz28
     |    rz33   rz34   rz35   rz36   rz37   rz38
     |            kzpsa1        BA350
     |------------------------------------------------------
     |      |      |      |      |      |      |
     |    rz28   rz28   rz28   rz28   rz28   rz28m 
     |    rz41   rz42   rz43   rz44   rz45   rz46
     |            kzpsa2        BA350
     |-----------------------------------------------------
     |      |      |      |      |      |      |
     |   rz28m  rz28m  rz28m  rz28m  rz28m  rz28m
     |   rz49   rz50   rz51   rz52   rz53   rz54
     |            kzpsa3        BA350
     |------------------------------------------------------
     |      |      |     
     |    tlz06  tlz06  
          



LSM mirrored volumes (one full disk is mirrored to another, the c partition)

    vol1    vol2     vol3     vol4     vol5     vol6     vol7     vol8
--------------------------------------------------------------------------
     |        |        |        |        |        |        |        |       
   rz2c     rz3c     rz4c     rz18c    rz19c    rz41c    rz42c    rz43c
   rz10c    rz11c    rz12c    rz34c    rz35c    rz49c    rz50c    rz51c ----->
                                                                        mirrors

    
               
    
774.5NABETH::alanDr. File System&#039;s Home for Wayward Inodes.Tue Apr 08 1997 21:1045
	The ISP controllers are Fast/Wide/Differential (and single-ended)
	SCSI adapters using the Qlogic ISP1020 chip(set).  One of the
	single-ended and three differential versions of this adapter are
	used in the KFTIA of the DEC 8200/8400 systems.  The KZPSA is a
	Fast/Wide/Differential adapter built around some NCR chip(set)
	(I think).

	Reorganizing your drawing we have:

	vol1
		rz2� - RZ28M at isp0
		rz10 - RZ28  at isp1

	vol2
		rz3  - RZ28M at isp0
		rz11 - RZ28  at isp1

	vol3
		rz4  - RZ28 at isp0
		rz12 - RZ28 at isp1

	vol6
		rz41 - RZ28  at kzpsa1
		rz49 - RZ28M at kzpsa2

	vol7
		rz42 - RZ28  at kzpsa1
		rz50 - RZ28M at kzpsa2

	vol8
		rz43 - RZ28  at kzpsa1
		rz51 - RZ28M at kzpsa2

	With the exception of vol3 all the volumes are made of pairs
	of RZ28s and RZ28Ms.  While these disks have the same capacity
	they aren't the same disk and the RZ28M may be faster in some
	circumstances.  For writing the I/O should be limited by the
	slower of the disks, but reads may perform differently.  Still,
	with the volume generally balanced between one of each it
	should even out, other things being equal.

	The remaining obvious differences are the ISPs vs. the KZPSAs
	and the BA350s vs. the BA356s.  You really need someone from
	the Storage Performance group to tell what the detailed
	differences are between the two adapters.
774.6Yes, that is true...HYDRA::LNARAYANWed Apr 09 1997 12:3713
    Hello
    
    Thank You for your attention.
    
>     The remaining obvious differences are the ISPs vs. the KZPSA
>     and the BA350s vs. the BA356s.  You really need someone from
>     the Storage Performance group to tell what the detailed
>     differences are between the two adapters.
    
    Exactly, I am looking for this information.