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CDM Alert showing 100% swap memory used on Linux


Article ID: 212465


Updated On:


DX Unified Infrastructure Management (Nimsoft / UIM)


We have an alert on 100% swap usage but our Linux administrator says it is not true and that there is no issue with swap memory. 



How is Swap Memory calculated by the CDM probe? 




Probe working as designed. 




Release : UIM 9.x / 20.x

Component : UIM - CDM Any version


As per the KB below:

UIM - Monitoring CDM memory usage on Linux


CDM reads the proc/meminfo file to obtain the memory usage qos data.

For example:



MemTotal:       65799664 kB
MemFree:          353572 kB
MemAvailable:     878784 kB
Buffers:           75020 kB
Active(anon):   58038964 kB
Inactive(anon):  5578888 kB
Active(file):     433240 kB
Inactive(file):   439508 kB
Unevictable:           0 kB
Mlocked:               0 kB
SwapTotal:       8191996 kB
SwapFree:              0 kB
Dirty:              2552 kB
Writeback:             0 kB



Looking at CDM.log:

In the CDM.logs we are seeing:


CDM-log we can see:

Apr  8 06:37:30:913 [140646738540352] cdm: (GetMemoryInfo) - swap total: 7999
Apr  8 06:37:30:913 [140646738540352] cdm: (GetMemoryInfo) - swap used: 7999

Apr  8 06:37:30:913 [140646738540352] cdm: (GetMemoryInfo) - Total: 72256 Physical: 64257 Swap: 7999
Apr  8 06:37:30:913 [140646738540352] cdm: (GetMemoryInfo) - Used : 68155 Physical: 60156 Swap: 7999

Apr  8 06:37:30:913 [140646738540352] cdm: CheckSwapAlarms
Apr  8 06:37:30:913 [140646738540352] cdm: Swap         [04] - val=7999MB avg=100%
Apr  8 06:37:30:913 [140646738540352] cdm: Swap         [04] - val=7999MB avg=100%,perc[100.000000]


Therefore the calulcation for Swap memory will be as below: 

QOS_MEMORY_SWAP (SwapUsed MB) = (SwapTotal - SwapFree) / 1024


In the case above:

SwapTotal:       8191996 kB - SwapFree:              0 kB = 100% used. 



In the above conditions, the CDM probe will create the alarm message correctly stating swap memory is 100%



Additional Information

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