Measure memory consumed by a container

[gomezgoiri]

• On creation.
• On normal operation (e.g., getting information from the instance).

[gomezgoiri]

References:

• Measuring memory usage in Linux
• How is memory usage reported in Linux?: virtual size (VIRT), resident size (RSS) & shared size (SHR).
• Why ps is "wrong"?
• Correctly determining memory usage in Linux
• Memory percentage: memPercent = float64(v.MemoryStats.Usage) / float64(v.MemoryStats.Limit) * 100.0

[gomezgoiri]

Basic measure on commit 29ed6df.

[gomezgoiri]

Stats response example:

"memory_stats":{
  "usage":310607872,
  "max_usage":344158208,
  "stats":{
    "active_anon":102088704,
    "active_file":11788288,
    "cache":208228352,
    "hierarchical_memory_limit":9223372036854775807,
    "hierarchical_memsw_limit":9223372036854775807,
    "inactive_anon":3219456,
    "inactive_file":193216512,
    "mapped_file":65257472,
    "pgfault":54140,
    "pgmajfault":700,
    "pgpgin":80280,
    "pgpgout":10140,
    "rss":102088704,
    "rss_huge":23068672,
    "swap":0,
    "total_active_anon":102088704,
    "total_active_file":11788288,
    "total_cache":208228352,
    "total_inactive_anon":3219456,
    "total_inactive_file":193216512,
    "total_mapped_file":65257472,
    "total_pgfault":54140,
    "total_pgmajfault":700,
    "total_pgpgin":80280,
    "total_pgpgout":10140,
    "total_rss":102088704,
    "total_rss_huge":23068672,
    "total_swap":0,
    "total_unevictable":0,
    "unevictable":0
  },
  "failcnt":0,
  "limit":134910681088
}

[gomezgoiri]

I have tried to tweak xvfb's configuration parameters and see how it would affect memory consumption.

To do this, I have used the same container and change supervisor.conf.

Although it seems that it affects it somehow, I could not obtain big improvements.

• Original configuration (1024x768x16):
  1. 197.4MB (10.23%)
  2. 192.4MB (9.97%)
• 1x1x8: 215MB (11.38%)
• 1x1x16:
  1. 195.8MB (10.15%)
  2. 189.4MB (9.81%)
  3. 193MB (10.00%)
  4. 190.8MB (9.88%)
• 1x1x24: 11.30%
• 100x100x8: 11.38%
• 1000x1000x8: 11.43%
• 1000x1000x16:
  1. 194.7 (10.25%)
  2. 1000x1000x16: 190.3 (9.86%)
  3. 1000x1000x16: 191.6 (9.86%)

Conclusions:

• The best depth seems to be 16.
• Using a lower the resolution, minor memory consumption improvements can be obtained.
• The usage of -fbdir /var/tmp always showed the same performance.
• Interacting with the webapp sometimes result in an minor increase of the memory usage.
• Attending to the variance obtained running the same commands in different moments, more tests should be done to check the significance of these appreciations.

[gomezgoiri]

I wonder whether making the window as small as possible also has effect on the memory consumption...

ipc.appWindow().setWindowGeometry(0,0,0,0);