PRIMECLUSTER Global File Services Configuration and Administration Guide 4.2 (Solaris(TM) Operating Environment)

25.1.1 Is the size of the update log area sufficient?

The GFS Shared File System delays writing from the update log buffer in memory to the update log area on the disk as much as possible. This delayed writing operation batches pieces of update log information about the same meta-data into a single block of information, minimizing the number of write operations of the updated log information. For efficiency of the delayed writing of the log, a sufficient update log area must be reserved.

In general, reserve a 1 megabytes update log area for every 100 megabytes of a file system. (This is the default setting of sfcnewfs(1M).)

The statistics command specific to the GFS Shared File System, sfcstat(1M), can be used to determine the average number of updates processed resulting from the updating of meta-data on the disk.

If the file system performance is low and the average is close to 1, try increasing the update log area.