asm_metrics

asm_metrics.pl main page

The asm_metrics.pl utility is used to display ASM real-time metrics. It basically takes a snapshot each second (default interval) from the gv$asm_disk_iostat (or gv$asm_disk_stat depending of the version) cumulative view and computes the delta with the previous snapshot.

This utility:

• provides useful metrics.
• is RAC aware.
• is fully customizable: you can aggregate the results depending on your needs.
• does not install anything into the database or ASM instance.

It displays the following metrics:

• Reads/s: Number of read per second.
• KbyRead/s: Kbytes read per second.
• Avg ms/Read: ms per read in average.
• AvgBy/Read: Average Bytes per read.
• Same metrics are provided for Write Operations.

At the following levels:

• ASM Instance.
• Database Instance.
• ASM Diskgroup.
• ASM Failgroup (Or cell’s IP on Exadata).
• Disks.

Let’s see the help:

./asm_metrics.pl -help

Usage: ./asm_metrics.pl [-interval] [-count] [-inst] [-dbinst] [-dg] [-fg] [-ip] [-show] [-display] [-sort_field] [-help]

 Default Interval : 1 second.
 Default Count    : Unlimited

  Parameter         Comment                                                           Default
  ---------         -------                                                           -------
  -INST=            ALL - Show all Instance(s)                                        ALL
                    CURRENT - Show Current Instance
                    INSTANCE_NAME,... - choose Instance(s) to display

  -DBINST=          Database Instance to collect (Wildcard allowed)                   ALL
  -DG=              Diskgroup to collect (Wildcard allowed)                           ALL
  -FG=              Failgroup to collect (Wildcard allowed)                           ALL
  -IP=              IP (Exadata Cells) to collect (Wildcard allowed)                  ALL
  -SHOW=            What to show: inst,dbinst,fg|ip,dg,dsk (comma separated list)     DG
  -DISPLAY=         What to display: snap,avg (comma separated list)                  SNAP
  -SORT_FIELD=      reads|writes|iops                                                 NONE

Example: ./asm_metrics.pl
Example: ./asm_metrics.pl  -inst=+ASM1
Example: ./asm_metrics.pl  -dg=DATA -show=dg
Example: ./asm_metrics.pl  -dg=data -show=inst,dg,fg
Example: ./asm_metrics.pl  -show=dg,dsk
Example: ./asm_metrics.pl  -show=inst,dg,fg,dsk
Example: ./asm_metrics.pl  -interval=5 -count=3 -sort_field=iops
Example: ./asm_metrics.pl  -show=dg -display=avg -sort_field=iops
Example: ./asm_metrics.pl  -show=dg -display=snap,avg -sort_field=iops

The main options/features are:

1. You can choose the number of snapshots to display and the time to wait between snapshots.
2. You can choose on which ASM instance to collect the metrics thanks to the –INST= parameter.
3. You can choose for which DB instance to collect the metrics thanks to the –DBINST= parameter (wildcard allowed).
4. You can choose on which Diskgroup to collect the metrics thanks to the –DG= parameter (wildcard allowed).
5. You can choose on which Failgroup to collect the metrics thanks to the –FG= parameter (wildcard allowed).
6. You can choose on which Exadata Cells to collect the metrics thanks to the –IP= parameter (wildcard allowed).
7. You can aggregate the results on the ASM instances, DB instances, Diskgroup, Failgroup (or Exadata cells IP) level thanks to the –SHOW= parameter.
8. You can display the metrics per snapshot, the average metrics value since the collection began (that is to say since the script has been launched) or both thanks to the –DISPLAY= parameter.
9. You can sort based on the number of reads, number of writes or number of IOPS (reads+writes) thanks to the –SORT_FIELD= parameter (See example here)

Examples:

IO activity reported for RAC ASM instances:

IO activity reported for ASM and database instances:

Visualize ASM preferred read in action and the associated metrics:

 

Blog posts related to it:

• ASM metrics are a gold mine. Welcome to asm_metrics.pl, a new utility to extract and to manipulate them in real time
• Find out the most physical IO consumers through ASM in real time
• Flex ASM 12c (12.1): be careful to “invisible” I/O !
• ASM I/O Statistics Utility V2
• Flex ASM 12c (12.1) and Extended Rac: be careful to “unpreferred” read !
• ASM Preferred Read: Collect performance metrics thanks to my amsiostat utility and SLOB 2
• ASM I/O Statistics Utility
• ASM Preferred Read: Collect performance metrics
• ASM I/O Statistics Utility: Update for Exadata

The last version of the asm_metrics.pl is 1.1

You can download it from this repository or copy the source code from this page.

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