Cached reads percentage too low
Hi,
I've recently started getting warnings to this effect in oncockpit.
I've only just started using oncockpit so the alarm is a standard one.
The alarm window reads;
Message
Cached reads percentage is too low
Alarm Data
Cached_reads :0
Criteria
cached_reads < 0.95
online 7.24.UC5
HP UX 10.20
roughly 80 to 100 users
dual processor K200 with 128Mb Ram, (+256Mb upgrade in the budget for next
year, (at the moment ;())
onstat -p
INFORMIX-OnLine Version 7.24.UC5 -- On-Line -- Up 16 days 19:11:49 --
176712 K
bytes
Profile
dskreads pagreads bufreads %cached dskwrits pagwrits bufwrits %cached
18746781 58344573 3687527753 99.49 3765414 45838208 35906714 89.51
isamtot open start read write
rewrite delete commit rollbk
1406859759 12309202 30675321 1257247580 5278376 288467 20090 179722
44
ovlock ovuserthread ovbuff usercpu syscpu numckpts flushes
0 0 0 308520.76 14926.20 2772 13680
bufwaits lokwaits lockreqs deadlks dltouts ckpwaits compress
seqscans
878336 355 3412322401 16 0 3858 704673
119667
ixda-RA idx-RA da-RA RA-pgsused lchwaits
3937466 21603 8993085 12872154 68674
onconfig
#**************************************************************************
#
# INFORMIX SOFTWARE, INC.
#
# Title: onconfig.misys1
# Description: INFORMIX-OnLine Configuration Parameters
#
# Raw devices are linked to files under /dev beginning online_
#
#**************************************************************************
# Root Dbspace Configuration
ROOTNAME rootdbs # Root dbspace nameROOTPATH /dev/online_root # Path for device containing root dbspace
ROOTOFFSET 0 # Offset of root dbspace into device
(Kbytes)
ROOTSIZE 100000 # Size of root dbspace (Kbytes)
# Disk Mirroring Configuration Parameters
MIRROR 1 # Mirroring flag (Yes = 1, No = 0)
MIRRORPATH # Path for device containing mirrored root
MIRROROFFSET 0 # Offset into mirrored device (Kbytes)
# Physical Log Configuration
PHYSDBS dbs_plog3 # Location (dbspace) of physical log
PHYSFILE 12000 # Physical log file size (Kbytes)
# Logical Log Configuration
LOGFILES 10 # Number of logical log files
LOGSIZE 4000 # Logical log size (Kbytes)
# Diagnostics
MSGPATH /var/adm/online.log # System message log file path
CONSOLE /dev/console # System console message path
ALARMPROGRAM /opt/informix/etc/log_full.sh # Alarm program path
# System Archive Tape Device
TAPEDEV /dev/rmt/0m # Tape device path
TAPEBLK 16 # Tape block size (Kbytes)
TAPESIZE 2000000 # Maximum amount of data to put on tape
(Kbytes)
# Log Archive Tape Device
LTAPEDEV /dev/null # Log tape device path
LTAPEBLK 16 # Log tape block size (Kbytes)
LTAPESIZE 2000000 # Max amount of data to put on log tape
(Kbytes)
# Optical
STAGEBLOB # INFORMIX-OnLine/Optical staging area
# System Configuration
SERVERNUM 1 # Unique id corresponding to a OnLineinstance
DBSERVERNAME live1 # Name of default database server
DBSERVERALIASES live2 # List of alternate dbservernames
NETTYPE ipcshm,1,250,CPU # Override sqlhosts nettype parameters
NETTYPE soctcp,1,,NET # Override sqlhosts nettype parameters
DEADLOCK_TIMEOUT 60 # Max time to wait of lock in distributed
env.
RESIDENT 0 # Forced residency flag (Yes = 1, No = 0)
MULTIPROCESSOR 1 # 0 for single-processor, 1 formulti-processor
NUMCPUVPS 1 # Number of user (cpu) vps
SINGLE_CPU_VP 1 # If non-zero, limit number of cpu vps toone
NOAGE 0 # Process aging
AFF_SPROC 0 # Affinity start processor
AFF_NPROCS 0 # Affinity number of processors
# Shared Memory Parameters
LOCKS 500000 # Maximum number of locks
BUFFERS 32000 # Maximum number of shared buffers
NUMAIOVPS 4 # Number of IO vps
PHYSBUFF 32 # Physical log buffer size (Kbytes)
LOGBUFF 32 # Logical log buffer size (Kbytes)LOGSMAX 25 # Maximum number of logical log files
CLEANERS 8 # Number of buffer cleaner processes
SHMBASE 0x0 # Shared memory base address
SHMVIRTSIZE 81928 # initial virtual shared memory segment size
SHMADD 8192 # Size of new shared memory segments
(Kbytes)
SHMTOTAL 0 # Total shared memory (Kbytes). 0=>unlimited
CKPTINTVL 200 # Check point interval (in sec)
LRUS 8 # Number of LRU queues
LRU_MAX_DIRTY 10 # LRU percent dirty begin cleaning limit
LRU_MIN_DIRTY 5 # LRU percent dirty end cleaning limit
LTXHWM 50 # Long transaction high water markpercentage
LTXEHWM 60 # Long transaction high water mark
(exclusive)
TXTIMEOUT 0x12c # Transaction timeout (in sec)
STACKSIZE 32 # Stack size (Kbytes)
# System Page Size
# BUFFSIZE - OnLine no longer supports this configuration parameter.
# To determine the page size used by OnLine on your platform
# see the last line of output from the command, 'onstat -b'.
# Recovery Variables
# OFF_RECVRY_THREADS:
# Number of parallel worker threads during fast recovery or an offline
restore.
# ON_RECVRY_THREADS:
# Number of parallel worker threads during an online restore.
OFF_RECVRY_THREADS 10 # Default number of offline workerthreads
ON_RECVRY_THREADS 1 # Default number of online worker threads
# Data Replication Variables
# DRAUTO: 0 manual, 1 retain type, 2 reverse type
DRAUTO 0 # DR automatic switchover
DRINTERVAL 30 # DR max time between DR buffer flushes (in
sec)
DRTIMEOUT 30 # DR network timeout (in sec)DRLOSTFOUND /opt/informix/etc/dr.lostfound # DR lost+found file path
# Read Ahead Variables
RA_PAGES 32 # Number of pages to attempt to read ahead
RA_THRESHOLD 8 # Number of pages left before next group
# DBSPACETEMP:
# OnLine equivalent of DBTEMP for SE. This is the list of dbspaces
# that the OnLine SQL Engine will use to create temp tables etc.
# If specified it must be a colon separated list of dbspaces that exist
# when the OnLine system is brought online. If not specified, or if
# all dbspaces specified are invalid, various ad hoc queries will cre
Your read cache rate seems to exceed the 95% specified, so i don't know why
you're getting the message.
My experience is that IDS benefits from KAIO on HP-UX. However, due to
general crapness of the product you can't safely run with KAIO enabled. I
seem to remember that you should have RESIDENT set to 1 for v7.24.
Neil
Tony Flaherty wrote in message
<920905471.1425.0.nnrp-02.c1ed1f69@news.demon.co.uk>...
>Hi,
> I've recently started getting warnings to this effect in oncockpit.
>I've only just started using oncockpit so the alarm is a standard one.
>
>The alarm window reads;
>
>Message
> Cached reads percentage is too low
>
>Alarm Data
> Cached_reads :0
>
>Criteria
> cached_reads < 0.95
>
>
>
>online 7.24.UC5
>HP UX 10.20
>roughly 80 to 100 users
>dual processor K200 with 128Mb Ram, (+256Mb upgrade in the budget for next
>year, (at the moment ;())
>
>onstat -p>
>INFORMIX-OnLine Version 7.24.UC5 -- On-Line -- Up 16 days 19:11:49 --
>176712 K
>bytes
>
>Profile
>dskreads pagreads bufreads %cached dskwrits pagwrits bufwrits %cached
>18746781 58344573 3687527753 99.49 3765414 45838208 35906714 89.51
>
>isamtot open start read write
>rewrite delete commit rollbk
>1406859759 12309202 30675321 1257247580 5278376 288467 20090 179722
>44
>
>ovlock ovuserthread ovbuff usercpu syscpu numckpts flushes
>0 0 0 308520.76 14926.20 2772 13680
>
>bufwaits lokwaits lockreqs deadlks dltouts ckpwaits compress
>seqscans
>878336 355 3412322401 16 0 3858 704673
>119667
>
>ixda-RA idx-RA da-RA RA-pgsused lchwaits
>3937466 21603 8993085 12872154 68674
>
>onconfig
>
>#**************************************************************************
>#
># INFORMIX SOFTWARE, INC.
>#
># Title: onconfig.misys1
># Description: INFORMIX-OnLine Configuration Parameters
>#
># Raw devices are linked to files under /dev beginning online_
>#
>#**************************************************************************
>
># Root Dbspace Configuration
>
>ROOTNAME rootdbs # Root dbspace name>ROOTPATH /dev/online_root # Path for device containing root dbspace
>ROOTOFFSET 0 # Offset of root dbspace into device
>(Kbytes)
>ROOTSIZE 100000 # Size of root dbspace (Kbytes)>
># Disk Mirroring Configuration Parameters
>
>MIRROR 1 # Mirroring flag (Yes = 1, No = 0)
>MIRRORPATH # Path for device containing mirrored root
>MIRROROFFSET 0 # Offset into mirrored device (Kbytes)>
># Physical Log Configuration
>
>PHYSDBS dbs_plog3 # Location (dbspace) of physical log
>PHYSFILE 12000 # Physical log file size (Kbytes)>
># Logical Log Configuration
>
>LOGFILES 10 # Number of logical log files
>LOGSIZE 4000 # Logical log size (Kbytes)>
># Diagnostics
>
>MSGPATH /var/adm/online.log # System message log file path
>CONSOLE /dev/console # System console message path
>ALARMPROGRAM /opt/informix/etc/log_full.sh # Alarm program path>
># System Archive Tape Device
>
>TAPEDEV /dev/rmt/0m # Tape device path
>TAPEBLK 16 # Tape block size (Kbytes)
>TAPESIZE 2000000 # Maximum amount of data to put on tape
>(Kbytes)>
># Log Archive Tape Device
>
>LTAPEDEV /dev/null # Log tape device path
>LTAPEBLK 16 # Log tape block size (Kbytes)
>LTAPESIZE 2000000 # Max amount of data to put on log tape
>(Kbytes)>
># Optical
>
>STAGEBLOB # INFORMIX-OnLine/Optical staging area
>
># System Configuration
>
>SERVERNUM 1 # Unique id corresponding to a OnLine>instance
>DBSERVERNAME live1 # Name of default database server
>DBSERVERALIASES live2 # List of alternate dbservernames
>NETTYPE ipcshm,1,250,CPU # Override sqlhosts nettype parameters
>NETTYPE soctcp,1,,NET # Override sqlhosts nettype parameters
>DEADLOCK_TIMEOUT 60 # Max time to wait of lock in distributed
>env.
>RESIDENT 0 # Forced residency flag (Yes = 1, No = 0)
>
>MULTIPROCESSOR 1 # 0 for single-processor, 1 for>multi-processor
>NUMCPUVPS 1 # Number of user (cpu) vps
>SINGLE_CPU_VP 1 # If non-zero, limit number of cpu vps to>one
>
>NOAGE 0 # Process aging
>AFF_SPROC 0 # Affinity start processor
>AFF_NPROCS 0 # Affinity number of processors>
># Shared Memory Parameters
>
>LOCKS 500000 # Maximum number of locks
>BUFFERS 32000 # Maximum number of shared buffers
>NUMAIOVPS 4 # Number of IO vps
>PHYSBUFF 32 # Physical log buffer size (Kbytes)
>LOGBUFF 32 # Logical log buffer size (Kbytes)>LOGSMAX 25 # Maximum number of logical log files
>CLEANERS 8 # Number of buffer cleaner processes
>SHMBASE 0x0 # Shared memory base address
>SHMVIRTSIZE 81928 # initial virtual shared memory segmentsize
>SHMADD 8192 # Size of new shared memory segments
>(Kbytes)
>SHMTOTAL 0 # Total shared memory (Kbytes).
0=>unlimited
>CKPTINTVL 200 # Check point interval (in sec)
>LRUS 8 # Number of LRU queues
>LRU_MAX_DIRTY 10 # LRU percent dirty begin cleaning limit
>LRU_MIN_DIRTY 5 # LRU percent dirty end cleaning limit
>LTXHWM 50 # Long transaction high water mark>percentage
>LTXEHWM 60 # Long transaction high water mark
>(exclusive)
>TXTIMEOUT 0x12c # Transaction timeout (in sec)
>STACKSIZE 32 # Stack size (Kbytes)>
># System Page Size
># BUFFSIZE - OnLine no longer supports this configuration parameter.
># To determine the page size used by OnLine on your platform
># see the last line of output from the command, 'onstat -b'.
>
>
># Recovery Variables
># OFF_RECVRY_THREADS:
># Number of parallel worker threads during fast recovery or an offline
>restore.
># ON_RECVRY_THREADS:
># Number of parallel worker threads during an online restore.
>
>OFF_RECVRY_THREADS 10 # Default number of offline worker>threads
>ON_RECVRY_THREADS 1 # Default number of online worker threads>
># Data Replication Variables
># DRAUTO: 0 manual, 1 retain type, 2 reverse type
>DRAUTO 0 # DR automatic switchover
>DRINTERVAL 30 # DR max time between DR buffer flushes (in
>sec)
>DRTIMEOUT 30 # DR network time
Just a wild guess. Your bufreads is above 2GIG. 2GIG is the point where an int becomes negative (i.e. 0x800000). If there is some spot where onperf is trying to map an unsigned int to an int, then it might be considering the cache rate to actually be negative. Just a guess.... Madison Pruet