IDS Forum

Re: Mapping cpuvp's to IBM virtual processors ....

Posted By: Dave Thacker
Date: Thursday, 22 February 2007, at 5:11 p.m.

In Response To: Re: Mapping cpuvp's to IBM virtual processors on p (ART KAGEL, BLOOMBERG/ 731 LEXIN)

On Thu, 2007-02-22 at 16:35 -0500, ART KAGEL, BLOOMBERG/ 731 LEXIN
wrote:
> Your assumption is partially correct. You don't NEED all 6 CPU's allocated to
> CPU VPs, but it's a good thing. The IDS scheduler will allocate sessions to
> CPU
> VPs as needed so it's possible that one or a few logical CPUS will be harder
> hit than the others. That said there are tunables that can affect that. For
> example if you are using shared memory connections to the instance you should
> have ipcshm poll threads running in all 6 CPU VPs or the load will not be
> balanced as well as it could be and responsiveness will suffer. I don't see
> any
> NETTYPE entries in the partial ONCONFIG you posted so you're probably running
> with the default of one poll thread.

NETTYPE is at default. Workload is 90% TCP/10$ SHM. What type of
threads should I add for soctcp?
>
> Also note that your instance is poorly tuned. BR is over 20 and values > 7
> indicate a slow server needing more LRUs and more CLEANERS (and possibly more
> BUFFERS). Your BTR (estimated since you didn't post any BUFFERS or BUFFERPOOL
> parameters) looks very high indicating that you may need more buffers.

I'm adding some more buffers tonight. All the data sits in 1 dbspace,
are more LRU's going to help?
>
> Can't tell much else based on your post alone.

What else do you need to see after I make this iteration?

DT

>
> Art S. Kagel
>
> ----- Original Message -----
> From: Dave Thacker <ids@iiug.org>
> At: 2/22 15:57:30
>
> We're currently running a read-only instance of IDS 10.0FC6 on AIX 5.3
> TL-05. The logical partition (LPAR) hosting IDS has 2.4 physical CPU's,
> divided into 6 logical CPU's. Running nmon's cpu monitor shows CPU 0
> at about 50% used, CPU1 used occasionally, and CPU 2-5 are idle. I'm
> assuming that my CPUVPS should equal the number of *logical* CPU's. Is
> that correct?
>
> IBM Informix Dynamic Server Version 10.00.FC6 -- On-Line -- Up 6
> days 00:13:54 -- 380512 Kbytes (stats were reset 105 minutes ago-DT)
>
> Profile
> dskreads pagreads bufreads %cached dskwrits pagwrits bufwrits
> %cached
> 542354 567359 107069044 99.49 12757 18870 100973
> 87.37
>
> isamtot open start read write rewrite delete
> commit rollbk
> 91733072 689270 7162014 62601768 8944 33817 8862
> 21144 0
>
> gp_read gp_write gp_rewrt gp_del gp_alloc gp_free
> gp_curs
> 0 0 0 0 0 0 0
>
> ovlock ovuserthread ovbuff usercpu syscpu numckpts flushes
> 0 0 0 1028.98 933.25 23 46
>
> bufwaits lokwaits lockreqs deadlks dltouts ckpwaits
> compress seqscans
> 144605 46 19779528 0 0 10 945
> 64620
>
> ixda-RA idx-RA da-RA RA-pgsused lchwaits
> 178985 16216 3 195178 6932
>
> ------
>
> excerpts from cat onconfig.usw
> # Root Dbspace Configuration
>
> ROOTNAME uswdbs # Root dbspace name
> ROOTPATH /usr/informix/links/uswdbs # Path for device
> containing root dbspace
> ROOTOFFSET 0 # Offset of root dbspace into device
> (Kbytes)
> ROOTSIZE 80000 # Size of root dbspace (Kbytes)
>
> # Disk Mirroring Configuration Parameters
>
> MIRROR 0 # Mirroring flag (Yes = 1, No = 0)
> MIRRORPATH # Path for device containing mirrored
> root
> MIRROROFFSET 0 # Offset into mirrored device (Kbytes)
>
> # Physical Log Configuration
>
> PHYSDBS uswdbs # Location (dbspace) of physical log
> PHYSFILE 4000 # Physical log file size (Kbytes)
>
> # Logical Log Configuration
>
> LOGFILES 8 # Number of logical log files
> LOGSIZE 2000 # Logical log size (Kbytes)
>
> # Tablespace Tablespace Configuration in Root Dbspace
>
> TBLTBLFIRST 0 # First extent size (Kbytes) (0 =
> default)
> TBLTBLNEXT 0 # Next extent size (Kbytes) (0 =
> default)
>
> # Security
> # DBCREATE_PERMISSION:
> # By default any user can create a database. Uncomment
> DBCREATE_PERMISSON to
> # limit database creation to a specific user. Add a new
> DBCREATE_PERMISSION
> # line for each permitted user.
>
> #DBCREATE_PERMISSION informix
>
> # DB_LIBRARY_PATH:
> # When loading a (C or C++) shared object (for a UDR or UDT), IDS checks
> that
> # the user-specified path starts with one of the directory prefixes
> listed in
> # the comma-separated list of prefixes in DB_LIBRARY_PATH. The string
> # "$INFORMIXDIR/extend" must be included in DB_LIBRARY_PATH in order for
> # extensibility and IBM supplied blades to work correctly.
>
> # DB_LIBRARY_PATH $INFORMIXDIR/extend
>
> # IFX_EXTEND_ROLE:
> # 0 (or off) => Disable use of EXTEND role to control who can register
> # external routines.
> # 1 (or on) => Enable use of EXTEND role to control who can register
> # external routines. This is the default behaviour.
> #
> IFX_EXTEND_ROLE 1 # To control the usage of EXTEND role.
>
> # Diagnostics
>
> MSGPATH /logs/online.usw.log # System message log file path
> CONSOLE /logs/online.cons.log # System console message path
>
> # To automatically backup logical logs, edit alarmprogram.sh and set
> # BACKUPLOGS=Y
> ALARMPROGRAM /usr/informix/etc/alarmprogram.sh # Alarm program path
> ALRM_ALL_EVENTS 0 # Triggers ALARMPROGRAM for any event
> occur
> TBLSPACE_STATS 1 # Maintain tblspace statistics
>
> # System Archive Tape Device
>
> TAPEDEV /dev/null # Tape device path
> TAPEBLK 32 # Tape block size (Kbytes)
> TAPESIZE 10240 # Maximum amount of data to put on tape
> (Kbytes)
>
> # Log Archive Tape Device
>
> LTAPEDEV /dev/null # Log tape device path
> LTAPEBLK 32 # Log tape block size (Kbytes)
> LTAPESIZE 10240 # Max amount of data to put on log tape
> (Kbytes)
>
> # Optical
>
> STAGEBLOB # Informix Dynamic Server staging area
>
> # System Configuration
>
> SERVERNUM 23 # Unique id corresponding to a OnLine
> instance
> DBSERVERNAME usw_tcp # Name of default database server
> DBSERVERALIASES usw # List of alternate dbservernames
> NETTYPE # Configure poll thread(s) for nettype
> 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 6 # 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 4000 # Maximum number of locks
> NUMAIOVPS 1 # Number of IO vps
> PHYSBUFF 64 # Physical log buffer size (Kbytes)
> LOGBUFF 64 # Logical log buffer size (Kbytes)
> CLEANERS 2 # Number of buffer cleaner processes
> SHMBASE 0x700000000000000L # Shared memory base address
> SHMVIRTSIZE 327680 # initial virtual shared memory segment
> size
> SHMADD 65336 # Size of new shared memory segments
> (Kbytes)
> EXTSHMADD 8192 # Size of new extension shared memory
> segments (Kbytes)
> SHMTOTAL 0 # Total shared memory (Kbytes).
> 0=>unlimited
> SHMVIRT_ALLOCSEG 0 # Values between 0 and .99 are %, values
> > 1 are
>
> # KB - when this much virtual memory is
> used we
>
> # try to get a new segment. 0 means
> "off". 2nd
>
> # parameter is alarm level
> CKPTINTVL 300 # Check point interval (in sec)
> TXTIMEOUT 300 # Transaction timeout (in sec)
> STACKSIZE 128 # Stack size (Kbytes)
>
> # Dynamic Logging
> # DYNAMIC_LOGS:
> # 2 : server automatically add a new logical log when necessary. (ON)
> # 1 : notify DBA to add new logical logs when necessary. (ON)
> # 0 : cannot add logical log on the fly. (OFF)
> #
> # When dynamic logging is on, we can have higher values for
> LTXHWM/LTXEHWM,
> # because the server can add new logical logs during long transaction
> rollback.
> # However, to limit the number of new logical logs being added,
> LTXHWM/LTXEHWM
> # can be set to smaller values.
> #
> # If dynamic logging is off, LTXHWM/LTXEHWM need to be set to smaller
> values
> # to avoid long transaction rollback hanging the server due to lack of
> logical
> # log space, i.e. 50/60 or lower.
> #
> # In case of system configured with CDR, the difference between LTXHWM
> and
> # LTXEHWM should be atleast 30% so that we could minimize log overrun
> issue.
>
> DYNAMIC_LOGS 2
> LTXHWM 70
> LTXEHWM 80
>
> # 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
>
> ------
>
> DT
>
> --
> Dave Thacker, Senior Systems Administrator
> Omni Hotels Reservation Center
> V: 402.952.6535 F: 402-334-8013 M: 402-981-4613 (24/7)
>
>
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>
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Messages In This Thread

• Re: Mapping cpuvp's to IBM virtual processors on p
  ART KAGEL, BLOOMBERG/ 731 LEXIN -- Thursday, 22 February 2007, at 4:35 p.m.
  • Re: Mapping cpuvp's to IBM virtual processors ....
    Dave Thacker -- Thursday, 22 February 2007, at 5:11 p.m.
    • Re: Mapping cpuvp's to IBM virtual processors ....
      ART KAGEL, BLOOMBERG/ 731 LEXIN -- Thursday, 22 February 2007, at 5:27 p.m.

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