Error 852

Severity

20

Message text

Command Failed: Invalid request to move '%ld'  buffers from the '%ld'K pool of the '%.*s' cache to the '%ld'K pool. Source  pool only contains '%ld' buffers. Retry the command specifying fewer buffers.

Explanation

The Cache Manager works in conjunction with the Buffer Manager to manage physical disk pages while they are in memory. When a page is read into memory from the disk, a buffer header is assigned to it. The header tracks the usage and the contents of the page image. The page and the buffer header together define a buffer.

The buffers themselves are grouped together to form memory address space segments (MASSes). A buffer cache consists of MASSes linked in MRU/LRU (most recently used/least recently used) chains. The Cache Manager manages MASSes and buffer caches.

The Adaptive Server command sp_poolconfig allows you to create, drop, resize, and get information about memory pools within named data caches. Error 852 occurs when you use sp_poolconfig or a configuration file to create or resize memory pool size and Adaptive Server is unable to find contiguous memory to fulfill the request.

Error 852 occurs with the following states:

State

Meaning

1

Error 852 occurs with state 1 when the size of the destination pool is smaller than the requested memory size.

2

Error 852 occurs with state 2 when the requested pool size is larger than the source pool size.

Action

  1. Use sp_cacheconfig to display information about the current configuration of the affected data cache and memory pools in the cache. For example:

    1> sp_cacheconfig test_cache
    2> go
    
    Cache Name    Status    Type     IO Sz  Wash Sz   Config Value Run Value 
    ------------- --------- -------- ------ --------- ------------ --------
    test_cache    Active    Mixed                          2.00 Mb 2.00 Mb
    test_cache    Active    Mixed      2 Kb    512 Kb      0.00 Mb 1.50 Mb
    test_cache    Active    Mixed      4 Kb    100 Kb      0.50 Mb 0.50 Mb
                                                      ------------ --------
                                                Total      2.00 Mb 2.00 Mb
    
    • The first line identifies the cache. Lines after the first line show defined memory pools.

    • The IO Sz column shows the I/O size for a memory pool.

    • The Config Value column shows the size the cache or pool will have after the next time Adaptive Server is restarted. If the value is 0, the size has not been explicitly configured and a default value will be used.

    • The Run Value column shows the size of the cache or pool now in use on Adaptive Server.

  2. Try the sp_poolconfig command again with appropriately-sized values or use sp_poolconfig to reconfigure the source pools to have an appropriate number of buffers available.

Additional information

Refer to the Reference Manual: Procedures for information about sp_cacheconfig and sp_poolconfig.

Versions in which this error is raised

All versions