Adaptive Server® Enterprise version 15.7 ESD #3 adds the estimate parameter to sp_helpconfig, which determines the approximate amount of memory required for certain memory-intensive configuration parameters.
Currently, the estimate parameter works only with the compression info pool size configuration parameter.
sp_helpcofig "config_name" [, { "size" | "estimate [using_argument = value [, using_argument = value ] [, ...] ] } ]
For example, maxconcusers = 0.7 indicates 70 percent of the configured value for number of user connections. An integer value of 1 or greater specifies an absolute number of concurrent users.
Issuing sp_helpconfig without arguments generates usage information, showing the subclauses you may specify, and some examples of typical usage.
sp_helpconfig 'compression info pool', 'estimate' The compression information pool size parameter indicates the amount of memory currently available to store table compression information. Minimum Value Maximum Value Default Value Current Value Memory Used Unit Type ------------- -------------- ------------- ------------- ----------- ---------------- ------- 0 2147483647 4096 4096 8240 memory pages(2k) dynamic Estimated memory required for 600 concurrent users requesting memory from this pool, accessing 500 compressed objects with 50 columns, on an average, per compressed table is 22600 KB. Configuration parameter, 'compression info pool size', can be configured to 21971 to fit in 44200K of memory.
sp_helpconfig 'compression info pool', 'estimate using numcompobjs=0.3, numtables=2.25, numcolumns=25, maxconcusers=0.85' The compression information pool size parameter indicates the amount of memory currently available to store table compression information. Minimum Value Maximum Value Default Value Current Value Memory Used Unit Type ------------- -------------- ------------- ------------- ----------- ---------------- ------- 0 2147483647 4096 4096 8240 memory pages(2k) dynamic Estimated memory required for 1020 concurrent users requesting memory from this pool, accessing 150 compressed objects with 25 columns, on an average, per compressed table is 37020 KB. Configuration parameter, 'compression info pool size', can be configured to 18402 to fit in 37020K of memory.
sp_configure 'user connections', 900 sp_configure 'worker processes', 500 sp_configure 'max parallel degree', 5
sp_helpconfig 'compression info pool size', 'estimate' The compression information pool size parameter indicates the amount of memory currently available to store table compression information. Minimum Value Maximum Value Default Value Current Value Memory Used Unit Type ------------- -------------- ------------- ------------- ----------- ---------------- ------- 0 2147483647 4096 15396 33384 memory pages(2k) dynamic Estimated memory required for 1400 concurrent users requesting memory from this pool, accessing 78240 compressed objects with 10 columns, on an average, per compressed table is 74850 KB. Configuration parameter, 'compression info pool size', can be configured to 34519 to fit in 74850K of memory.
This output indicates that a total of 1400 concurrent users are expected to simultaneously request memory. The database has slightly more than 78000 compressed objects, with each table having, on average, 10 columns. The estimated value for this configuration option is 34519.
sp_helpconfig 'compression info pool size', 'estimate using numcompobjs = 50000, maxconcusers=600' The compression information pool size parameter indicates the amount of memory currently available to store table compression information. Minimum Value Maximum Value Default Value Current Value Memory Used Unit Type ------------- -------------- ------------- ------------- ----------- ---------------- ------- 0 2147483647 4096 15396 33384 memory pages(2k) dynamic Estimated memory required for 1100 concurrent users requesting memory from this pool, accessing 50000 compressed objects with 10 columns, on an average, per compressed table is 55225 KB. Configuration parameter, 'compression info pool size', can be configured to 25468 to fit in 55225K of memory.
In this output, maxconcusers = 600 implies that 600 concurrent client connections are accessing compressed objects requesting memory. Because of the parallel configuration settings, sp_helpconfig estimates that a total of 1100 requesters may concurrently request memory. The estimated value for this configuration option is 25468.