Re: Long checkpoints : IDS and SCO
one way to counteracct the effects of long checkpoints is to have them more often. You can tune the
LRU_MAX_DIRTY and LRU_MIN_DIRTY parameters (make them smaller) so that the LRUs are flushed more often.
cl wrote:
> Details :
> servers : ml570 4 proc (xeon933) 2Go RAM , SCO Open Server 5.06a
> Informix : IDS 731UC5
>
> PB : the checkpoints are very long and the server slows down.
>
> onstat -u>
> Informix Dynamic Server Version 7.31.UC5 -- On-Line -- Up 11 days
> 02:31:18 -- 241664 Kbytes
>
> Userthreads
> address flags sessid user tty wait tout locks nreads
> nwrites
> 16c56014 ---P--D 1 root - 0 0 0 6526
> 109749
> 16c564fc ---P--F 0 root - 0 0 0 0
> 337312
> 16c569e4 ---P--F 0 root - 0 0 0 0
> 1543339
> 16c56ecc ---P--F 0 root - 0 0 0 0
> 1483882
> 16c573b4 ---P--F 0 root - 0 0 0 0
> 187020
> 16c5789c ---P--F 0 root - 0 0 0 0
> 9540
> 16c57d84 ---P--F 0 root - 0 0 0 0
> 19742
> 16c5826c ---P--F 0 root - 0 0 0 0
> 30219
> 16c58754 ---P--F 0 root - 0 0 0 0
> 20492
> 16c58c3c ---P--- 17 root - 0 0 0 0
> 246
> 16c59124 ---P--B 18 root - 0 0 0 43
> 0
> 16c5960c Y--P--- 147496 toto - 19ed72bc 0 1 12 0
> 16c59af4 Y--P--- 147091 titi - 19e0df30 0 1 7059
> 65
> 16c59fdc ---P--D 46 root - 0 0 0 3168
> 0
> *************************************************************************************************************
> 1ee7a9ac Y--P--- 140791 titi - 172fa2f4 0 1 3036
> 65
> 1ee7bd4c Y--P--- 144385 toto - 1a9df028 0 1 66073 0
> 1ee7c71c Y--P--- 146707 toto - 16efd2bc 0 1 6104 0
> 1ee7d0ec Y--P--- 145671 toto ttyp36 1ab7b22c 0 1 3956 0
> 360 active, 512 total, 410 maximum concurrent
>
> onconfig
>
> #**************************************************************************
> #
> # INFORMIX SOFTWARE, INC.
> #
> # Title: onconfig.ows
> # Description: INFORMIX-OnLine Configuration Parameters
> #
> #**************************************************************************
> # Root Dbspace Configuration
> ROOTNAME rootdbs # Root dbspace name
> ROOTPATH /u/informix/IFMXDATA/toto/ROOTDBS.000
> ROOTOFFSET 0 # Offset of root dbspace into device
> (Kbytes)
> ROOTSIZE 100000 # Size of root dbspace (Kbytes)> # Disk Mirroring Configuration Parameters
> MIRROR 0 # Mirroring flag (Yes = 1, No = 0)
> MIRRORPATH
> MIRROROFFSET 0 # Offset into mirrored device (Kbytes)> # Physical Log Configuration
> PHYSDBS rootdbs # Location (dbspace) of physical log
> PHYSFILE 10000 # Physical log file size (Kbytes)> # Logical Log Configuration
> LOGFILES 6 # Number of logical log files
> LOGSIZE 1000 # Logical log size (Kbytes)> # Diagnostics
> MSGPATH /u/informix/online.log # System message log file path
> CONSOLE /dev/null # ne pas afficher les messages
> ALARMPROGRAM /u/informix/etc/log_full.sh # Alarm program path> # System Archive Tape Device
> TAPEDEV /dev/nrct0
> TAPEBLK 16 # Tape block size (Kbytes)
> TAPESIZE 4000000 # Maximum amount of data to put on
> tape (Kbytes)> # Log Archive Tape Device
> LTAPEDEV /dev/null
> 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 0 # Unique id corresponding to a OnLine> instance
> DBSERVERNAME toto # Name of default database server
> DBSERVERALIASES toto_tli # List of alternate> dbservernames
> NETTYPE ipcshm,3,160,CPU
> NETTYPE tlitcp,1,20,NET
> 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 3 # Number of user (cpu) vps
> SINGLE_CPU_VP 0 # 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 25000 # Maximum number of locks
> BUFFERS 50000 # Maximum number of shared buffers
> NUMAIOVPS 8 # Number of IO vps
> PHYSBUFF 128 # Physical log buffer size (Kbytes)
> LOGBUFF 32 # Logical log buffer size (Kbytes)> LOGSMAX 6 # Maximum number of logical log files
> CLEANERS 8 # Number of buffer cleaner processes
> SHMBASE 0x10000000 # Shared memory base address
> SHMVIRTSIZE 32768 # initial virtual shared memory> segment size
> SHMADD 16384 # Size of new shared memory segments
> (Kbytes)
> SHMTOTAL 0 # Total shared memory (Kbytes).
> 0=>unlimited
> CKPTINTVL 300 # Check point interval (in sec)
> LRUS 8 # Number of LRU queues
> LRU_MAX_DIRTY 60 # LRU percent dirty begin cleaning> limit
> LRU_MIN_DIRTY 50 # LRU percent dirty end cleaning limit
> LTXHWM 50 # Long transaction high water mark> percentage
> LTXEHWM 60 # Long transaction high water mark
> (exclusive)
> TXTIMEOUT 300 # 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@@