Avoiding buffer manager thrashing
476
2 0
137 0
22 0
203 3
Example of -threads
option
The results of the
-threads
option look like the following:
Options string for Main cache: "-threads -file_suffix threads-iqmon -append
-interval 10"
Threads
2000-01-24 10:59:24
CPUs Limit NTeams MaxTms NThrds Resrvd Free Locks Waits
10 100 4 12 100 13 68 106 590
10 100 6 12 100 12 63 4 6
10 100 6 12 100 12 63 0 0
10 100 7 12 100 12 62 1 1
10 100 7 12 100 12 62 0 0
10 100 7 12 100 12 58 1 5
10 100 7 12 100 12 58 0 0
Avoiding buffer manager thrashing
Operating system paging affects queries that need buffers which exceed the
free memory available. Some of this paging is necessary, especially as you
allocate more and more physical memory to your buffer caches. However, if
you overallocate the physical memory to your buffer caches, the operating
system paging occurs much more frequently, and it can cause your entire
system to thrash. The reverse is true as well: IQ thrashes if you do not allocate
enough memory to your buffer caches.
Summary of Contents for Adaptive Server IQ 12.4.2
Page 1: ...Administration and Performance Guide Adaptive Server IQ 12 4 2 ...
Page 16: ...xvi ...
Page 20: ...Related documents xx ...
Page 40: ...Compatibility with earlier versions 20 ...
Page 118: ...Troubleshooting startup shutdown and connections 98 ...
Page 248: ...Importing data by replication 228 ...
Page 306: ...Integrity rules in the system tables 286 ...
Page 334: ...Cursors in transactions 314 ...
Page 396: ...Users and permissions in the system tables 376 ...
Page 438: ...Determining your data backup and recovery strategy 418 ...
Page 484: ...Network performance 464 ...
Page 500: ...System utilities to monitor CPU use 480 ...
Page 514: ...Characteristics of Open Client and jConnect connections 494 ...
Page 536: ...Index 516 ...