Displays many key buffer cache and memory manager locks. These lock and mutex counters show the activity within the buffer cache and heap memory and how quickly these locks were resolved. Timeout numbers that exceed 20% indicate a problem.
monitor_options -contention
Output field |
Description |
|---|---|
AU |
Current number of active users |
LRULks |
Number times the LRU was locked (repeated for the temp cache) |
woTO |
Number times lock was granted without timeout (repeated for the temp cache) |
Loops |
Number times Sybase IQ retried before lock was granted (repeated for the temp cache) |
TOs |
Number of times Sybase IQ timed out and had to wait for the lock (repeated for the temp cache) |
BWaits |
Number of Busy Waits for a buffer in the cache (repeated for the temp cache) |
IOLock |
Number of times Sybase IQ locked the compressed I/O pool (repeated for the temp cache); can be ignored |
IOWait |
Number of times Sybase IQ had to wait for the lock on the compressed I/O pool (repeated for the temp cache); can be ignored |
HTLock |
Number of times Sybase IQ locked the block maps hash table (repeated for the temp cache) |
HTWait |
Number of times Sybase IQ had to wait for the block maps hash table (repeated for the temp cache); HTLock and HTWait indicate how many block maps you are using |
FLLock |
Number of times Sybase IQ had to lock the free list (repeated for the temp cache) |
FLWait |
Number of times Sybase IQ had to wait for the lock on the free list (repeated for the temp cache) |
MemLks |
Number of times Sybase IQ took the memory manager (heap) lock |
MemWts |
Number of times Sybase IQ had to wait for the memory manager lock |
Due to operating system improvements, Sybase IQ no longer uses spin locks. As a result, the woTO, Loops, and TOs statistics are rarely used.