CHAPTER 13 Monitoring and Tuning Performance

•Reads/Writes: Physical reads and writes performed by the buffer cache

•PF/PFRead: Prefetch requests and reads done for prefetch

•GDirty: Number of times the LRU buffer was grabbed dirty and Adaptive Server IQ had to write it out before using it

•Pin%: Percentage of pages in the buffer cache in use and locked

•Dirty%: Percentage of buffer blocks that were modified

•-cache_by_typeproduces the same results as -cache, but broken down by IQ page type. (An exception is the Bwaits column, which shows a total only.) This format is most useful when you need to supply information to Sybase Technical Support.

•-file_suffixsuffix creates a monitor output file named

<dbname>.<connid>-<main_or_temp>-<suffix>. If you do not specify a suffix, it defaults to iqmon.

•-iodisplays main or temp (private) buffer cache I/O rates and compression ratios. The fields displayed are:

•Reads: Physical reads performed by the buffer cache

•Lrd(KB): Logical kilobytes read in

•Prd(KB): Physical kilobytes read in

•Rratio: Compression ratio of logical to physical data read in

•Writes: Physical writes performed by the buffer cache

•Lwrt(KB): Logical kilobytes written

•Pwrt(KB): Physical kilobytes written

•Wratio: Compression ratio of logical to physical data written

•-bufallocdisplays information on the main or temp buffer allocator, which reserves space in the buffer cache for objects like sorts, hashes, and bitmaps.

•OU: OptimizeForThisManyUsers option setting

•AU: Current number of active users

•MaxBuf: Number buffers under control of the buffer allocator

•Avail: Number of currently available buffers for pin quota allocation

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