How to know the size of database cache (global buffer) in use |

Article

Megumi Kakechi · Oct 19, 2023 2m read

#ObjectScript #Tips & Tricks #Tools #Caché #Ensemble #InterSystems IRIS #InterSystems IRIS for Health

InterSystems FAQ rubric

A tool (^GLOBUFF utility) is available to check the database cache usage for each global variable.

You can run the utility directly or programmatically in the %SYS namespace.

Here's how to run the utility directly:

USER>zn "%SYS"

%SYS>do ^GLOBUFF

Find which globals are using the most buffers.

Display the top <25>: → Press Enter // Default is to display top 25 globals

Total buffers: 102400 Buffers in use: 6926 PPG buffers: 77 (1.112%) // Global name, database name, percentage occupied by the buffer

Item Global Database Percentage (Count)
1 oddDEF IRISLIB 34.551 (2393)
2 rOBJ IRISLIB 15.261 (1057)
3 rOBJ IRISSYS 13.630 (944)
：

The way to run it programmatically is as follows.

  set log="C:\temp\g.log"
  open log:"WNS"
  use log
  do display^GLOBUFF(200)
  close log

The execution result will be as follows.

Total buffers: 102400 Buffers in use: 6926 PPG buffers: 77 (1.112%)

Item Global Database Percentage (Count)
1 oddDEF IRISLIB 34.551 (2393)
2 rOBJ IRISLIB 15.261 (1057)
3 rOBJ IRISSYS 13.630 (944)
：

Go to the original post written by @Megumi Kakechi