solidDB Help : Configuring and administering : Monitoring solidDB : Monitoring memory consumption
  
Monitoring memory consumption
The in-memory database main memory usage differs from the standard solidDB memory usage. The in-memory database resides in its own memory pool.
You must pay special attention to controlling memory consumption:
▪ If the in-memory database or the server process uses up all of the available virtual memory in the system, you are unable to add or update data.
▪ If the server uses up all of the physical memory and starts to use virtual memory, the server continues to operate, but performance is greatly reduced.
The solidDB main memory engine provides commands and configuration parameters to help you monitor and control the memory consumption of the in-memory database and the server process. These commands and parameters focus on the in-memory database feature of the server, not the server as a whole.
The following table describes a number of ADMIN COMMANDs that you can use to monitor memory consumption.
For information on controlling memory consumption, see Controlling memory consumption.
 
ADMIN COMMAND
Description
See:
'info imdbsize'
Returns the current amount of memory allocated to in-memory database tables and indexes. The value indicates the number of kilobytes used by the server. The command returns the amount of virtual memory used, not the amount of physical memory used.
In time, the value of imdbsize can grow, because returning memory to the operating system can only be done in allocation units, which need to be completely unused before they can be returned.
Transient memory allocations (such as SQL execution graphs) are excluded from the ADMIN COMMAND 'info imdbsize' report.
'info processsize'
Returns the virtual memory process size (the full address space size) of the database server that the in-memory database process uses. The value returned is a VARCHAR, and it indicates the number of kilobytes used by the process. This command returns the amount of virtual memory used, not the amount of physical memory used.
'pmon mme'
Produces the following list of current values of counters:
RC TEXT
-- ----
0 Performance statistics:
0 Time (sec) 30 21 Total
0 MME current number of locks : 0 0 0
0 MME maximum number of locks : 0 0 0
0 MME current number of lock chains : 0 0 0
0 MME maximum number of lock chains : 0 0 0
0 MME longest lock chain path : 0 0 0
0 MME memory used by tuples : 0 0 0
0 MME memory used by indexes : 0 0 0
0 MME memory used by page structures: 0 0 0
10 rows fetched.
In the performance statistics listing, the amount of memory used by tuples, indexes, and page structures is given in KB.
PERFMON
'memory'
Reports the amount of dynamically allocated heap memory. In heap-based memory allocation, memory is allocated from a large pool of unused memory area called the heap. The size of the heap memory allocation can be determined at runtime. Transient memory allocations (such as SQL execution graphs) are included in the ADMIN COMMAND 'memory' report.
MEMORY
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