Re: Checkpoint duration increase with 7.22.UC1
Hi David,
CLEANERS are set to 80. Amount of KB to write during the checkpoint
will be 6880 KB, must be appr. 6.5MB.
I don't know anything about their disk layout. But if they have
more than one chunk per disk and if they are using KAIO, then
they risk parallel writing to one disk.
I'm sure you will help this guy,
have a nice day
bye
Stefan
David Williams wrote:
>
> In article <5lak28$ssn@cssun.mathcs.emory.edu>, Kernoal Stephens
> <kernoals@earthlink.net> writes
> >I recently upgraded from 7.13.UC2 to 7.22.UC1.
> >
> >With 7.13.UC2 my checkpoint duration was averaging 4.5 seconds.
> >I used the same onconfig settings with 7.22.UC1 and my average
> >checkpoint duration
> >is 8.4 seconds.
> >
> >I am not using any of the new tools yet (i.e. HPloader, ONbar, CDR).
> >
> >I am 99% OLTP and have spent three months getting my checkpoint to under
> >5 seconds with 7.13.
> >
> >What has changed to cause the checkpoint duration to increase?
>
> Possibly just that Onine has got bigger due to more features..
> >
> >Thanks
> >kernoals@earthlink.net
> >Kernoal Stephens
> >First Data Corporation
> >Tulsa
> >
> >Server: 1000e, Solaris 2.5, 8CPUs, 640MB, KAIO, Raw Disks.
> >Dedicated Online Database Server.
> >
> Check OPTCOMPIND = 0 and was not changed to 2 when you upgraded...
> the installation program for Online changes this and does not tell
> you...
>
> >ONCONFIG FILE
> >#####################
> >
> >MULTIPROCESSOR 1
> >NUMCPUVPS 7
> >SINGLE_CPU_VP 0> >
> Good - 7 CPU VPs.
>
> >NOAGE 1
> >AFF_SPROC 0
> >AFF_NPROCS 0> >
> Try setting these to 1/7 i.e. use affinity.
>
> ># Shared Memory Parameters
> >
> >LOCKS 200000
> >BUFFERS 172032
> >NUMAIOVPS 2> Since all disks are KAIO you only need 1 AIOVPs to write to o
> online.log and the console.
>
> >PHYSBUFF 96
> >LOGBUFF 32> >LOGSMAX 400
> >CLEANERS 80
> >SHMBASE 0xa000000
> >SHMVIRTSIZE 137728
> >SHMADD 8192> Run onstat -g seg and check you only have one virtual segment
> of shared memory..possibly you need to increase SHMVIRTSIZE..
>
> >SHMTOTAL 0
> >CKPTINTVL 600
> >LRUS 14
> LRUS should = NUMCPUVPS i.e. 7.
>
> >LRU_MAX_DIRTY 2
> >LRU_MIN_DIRTY 1
> Good.
>
> >LTXHWM 50
> >LTXEHWM 60
> >TXTIMEOUT 0x12c
> >STACKSIZE 32> >
> ># Read Ahead Variables
> >RA_PAGES 24
> >RA_THRESHOLD 16> >
> >DBSPACETEMP tmpspace40,tmpspace40m,tmpspace21,tmpspace21m
> >
> >
> ># Parallel Database Queries (pdq)
> >MAX_PDQPRIORITY 25
> >DS_MAX_QUERIES 50
> >DS_TOTAL_MEMORY 113152
> >DS_MAX_SCANS 1048576
> >DATASKIP off>
> Where are the other entries in ONCONFIG e.g. CLEANERS???
>
> --
> David Williams