Monitoring memory usage within the cluster caching facility server process
The CF_MEM_SZ cluster caching facility (also known as a CF) memory configuration parameter controls the maximum size that the CF process can grow to. When the CFs starts up, using memory tracking utilities such as svmon, will not show a large change in used memory because the full allocation is not yet committed or backed by real memory. Memory is only committed or backed when it is accessed for the first time. As more databases are activated and database activities take place, more memory is committed in order to keep track of the activities until the maximum CF memory size is reached.
The memory for certain structures persist until a database is dropped or the CF server is stopped therefore the memory might persist as shown in svmon output.
Memory size (4KB) (CF_MEM_SZ) = AUTOMATIC(33874432)
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 6168 dtw 20 0 0.132t 9.498g 9.223g S 2988.2 5.028 178819:52 ca-server 3070 root 20 0 841600 3128 2512 S 5.882 0.002 7:13.75 nscd 4135 root 20 0 433752 45292 19032 S 5.882 0.023 1544:02 BESClient 6652 dtw 20 0 15644 3020 2272 R 5.882 0.002 0:00.02 top
CF Server (128) Information Hostname = coralm215.torolab.ibm.com Management Port = 27727 Role = Primary CF Host Information Virtual Memory Used = 18793431040 Virtual Memory Available = 188314128384 Real Memory Used = 18793431040 Real Memory Available = 184012312576 Swap File Used = 0 Swap File Available = 4301815808 CPU Usage = 0 CPU Activity = 97 Total structure memory (4KB) = 34626048 Free structure memory (4KB) = 2724096 Memory frame Size (4KB) = 256 Configured Size (4KB) = 34626048 Current Worker Queue Size = 0 Minimum Worker Queue Size = 0 Maximum Worker Queue Size = 1 Average Worker Queue Size = 0
Group Bufferpool Information Structure Name = db2.dtw.DTW.gbp SID = 316 Current Size (4KB) = 1260227 Target Size (4KB) = 30700032 Configured Size (4KB) = 30700032 CF Driven Castout = 0 Shared Communication Area Information Structure Name = db2.dtw.DTW.sca SID = 314 Current Size (4KB) = 5198 Target Size (4KB) = 58624 Configured Size (4KB) = 58624 List Structure / Smart Array Information Structure Name = db2.dtw.DTW.list SID = 337 Current Size (4KB) = 14339 Target Size (4KB) = 141568 Configured Size (4KB) = 141568 Lock Structure Information Structure Name = db2.dtw.DTW.lock SID = 318 Current Size (4KB) = 249742 Target Size (4KB) = 1000192 Configured Size (4KB) = 1000192