Benchmarking Objects

When the performance of a subset of such Performance Toolkit objects as users, I/O devices, ISFC logical links, ISFC end points, or PCI functions should be investigated more closely, a log-type display with performance data for a specific object on a "per sample" basis can provide help with analyzing the behavior of such an object.

To keep storage requirements and data collection overhead low, such log files are not created automatically. You can instruct Performance Toolkit to build log files for selected objects by using the FC BENCHMRK command. See the FCONTROL BENCHMRK subcommand in the z/VM: Performance Toolkit Reference for more information.

Log files will then be built for each selected object, with one entry per sample interval.

After benchmarking has been activated, you can select a benchmark overview menu that shows the logs currently being built. The following is an example of such a display.
Figure 1. Benchmark Log Selection Menu
 
FCX173      CPU nnnn  SER nnnnn        BENCHMRK Log Data         Perf. Monitor 
______    .
  Object    Log File
S ID        Name       Description
. CFT2NDA   ISFLLOG    ISFC Logical Link activity log        
. LXA00001  UCOMMLOG   User IUCV and VMCF communications log 
. LXA00001  UPAGELOG   User paging load log                  
. LXA00001  URESPLOG   User response time log                
. LXA00001  USERLOG    User resource consumption log         
. LXA00001  USTATLOG   User wait state log                   
. LXA00001  UTRANLOG   User resources per transaction log    
. RSTL3     UCOMMLOG   User IUCV and VMCF communications log 
. RSTL3     UPAGELOG   User paging load log                  
. RSTL3     URESPLOG   User response time log                
. RSTL3     USERLOG    User resource consumption log         
. RSTL3     USTATLOG   User wait state log                   
. RSTL3     UTRANLOG   User resources per transaction log    
. TCPIP     MTUSRLOG   User multitasking data log            
. TCPIP     UCOMMLOG   User IUCV and VMCF communications log 
. TCPIP     UPAGELOG   User paging load log                  
. TCPIP     UQDIOLOG   User QDIO activity log                
. TCPIP     URESPLOG   User response time log                
. TCPIP     USERLOG    User resource consumption log         
. TCPIP     USTATLOG   User wait state log                   
. TCPIP     UTRANLOG   User resources per transaction log    
. 00000001  ISFELOG    ISFC End Point activity log           
. 2A60      CACHDLOG   I/O device CU cache data log          
. 2A60      CACHELOG   Extended function cache data log      
. 2A60      CPOWNLOG   CPOWNed I/O device log                
. 2A60      DEVLOG     General I/O device performance log    
. 2B20      DEVLOG     General I/O device performance log    
. 2B20      HPFLOG     HPF I/O device activity log 
. 4000      DEVLOG     General I/O device performance log
. 4000      HPFLOG     HPF I/O device activity log   
. 4000      VOLLOG     DASD Volume performance log
 
 Select an object log with cursor and hit ENTER
 Command ===> _
 F1=Help  F4=Top  F5=Bot  F7=Bkwd  F8=Fwd  F12=Return
This example shows the types of logs that might be generated when benchmarking has been activated for users LXA00001, RSTL3, and TCPIP, for I/O devices 2A60, 2B20, and 4000, for ISFC endpoint 1, and for ISFC logical link CFT2NDA. Log file creation depends on the existence of the following:
  • Monitor domains that are activated for the user, I/O device, logical link, or endpoint
  • The user, I/O device, ISFC logical link, or ISFC endpoint existence itself.
Note the following in Figure 1:
  • The absence of seeks data for all I/O devices, because SEEKS event data collection was probably not enabled.
  • The device 2A60 has cache data logs, because the disk was connected to a cache control unit.
  • CPOWNLOG has been built, because that disk contains system areas.
  • Other devices have general I/O logs only, because these devices are not disks.
  • The benchmarked device 2B20 is a HyperPAV alias that generates multiple benchmark logs, including DEVLOG and HPFLOG.
  • The benchmarked device 4000 is a HyperPAV base that generates multiple benchmark logs, including DEVLOG, HPFLOG, and VOLLOG.
  • The benchmarked user LXA00001 is running on a virtual IFL processor and multithreading is enabled for the system that provided the data.

The logs are initially sorted by object ID. You can change the sequence to have them sorted by the log name instead.

Field Descriptions:

S
The cursor selection field.
Object ID
The object for which performance is logged. An object can be a user ID, a device number of I/O device, an ISFC logical link name, an ISFC end point ID, or a PCI function ID, for example.
Log File Name
The command with which the log data can be selected for display.
Description
The log file description.