Sybase 12.4.2 manual System utilities to monitor CPU use, 479

CHAPTER 13 Monitoring and Tuning Performance

19 0 0 3246612 26748 0 273 1248 0 0 0 0 950 394 1180 92 7 0

The above output is from slightly later when the query is underway. This is evident from the user mode CPU level (us field). The buffer cache is not yet full as page-in faults (pi field or KB paged in) are still occurring and the amount of free memory is still going down.

procs			memory				page						faults			cpu
r	b	w swap		free	re mf pi			po	fr	de sr		in	sy	cs	us sy id
21	0	0	3246608	22100	0	201	1600	0	0	0	0	1208	1257	1413	88	12	0
18	0	0	3246608	17196	0	370	1520	0	464	0	139	988	209	1155	91	8	0
11	0	0	3251116	16664	0	483	2064	138	2408	0	760	1315	218	1488	88	12	0
30	0	0	3251112	15764	0	475	2480	310	4450	0	1432	1498	199	1717	87	13	0

The above output is from even later. On the third line of the output it shows that the system has reached its threshold for the amount of free memory it can maintain. At this point, page-outs (po field or KB paged out) occur and the level of system mode CPU (sy field) increases accordingly. This situation results because physical memory is overallocated: the Adaptive Server IQ buffer caches are too big for the machine. To resolve this problem, reduce the size of one or both of the buffer caches.

System utilities to monitor CPU use

Use these operating system utilities to monitor CPU usage while using

Adaptive Server IQ. On UNIX systems use:

•ps command

•vmstat command (see example in the previous section)

•sar command (UNIX SystemV)

On Windows NT systems use:

•Performance Monitor

•Task Manager

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