The IQ temporary store blocks message displays information about use of the blocks and buffers in the IQ temporary store.
This line in the IQ message log (.iqmsg file) describes the Temporary IQ Store:
Temporary Blks: U273/0%, Buffers: U1987/L1960
Item |
Description |
|---|---|
U# |
Number of blocks in use. |
#% |
Percentage of database filled. |
Buffers: U# |
Number of buffers in use. Normally, this is 100% because the buffer manager leaves buffers in memory until they are needed for some other data. In general, the buffers used and buffers locked numbers are meaningless, because IQ uses buffers as aggressively and efficiently as it can. Objects in the temporary cache release their buffers when they are finished. |
L# |
Number of locked buffers. A locked buffer is in use and cannot be removed from the cache. IQ locks buffers of some objects, such as hash objects, to keep them in memory. It locks buffers of other objects, such as sorts, depending on the workload and what it considers a fair share for that object. This number increments when you request a buffer. If you exceed the maximum while running a script, the command that exceeds it fails and subsequent commands may complete incorrectly. Buffer locks do not use any memory. A locked buffer has a flag set in the in-memory structure and the flag exists whether or not the buffer is locked. |
It is important that you recognize when the server is low on disk space and adding a new dbspace before the server runs out of space is important. For an example of using an event handler to monitor disk space usage and to notify you when available space is low during a load, see Monitoring disk space usage.