[Ganglia] RRAs 설정 예제.

[원문]

http://www.perzl.org/ganglia/bestpractices.html

Best Practices – Ganglia Sampling Intervals

Important to know:

• The sampling interval is defined in /etc/gmetad.conf.
• The "RRAs" stanza is used to defined individual settings.
• The sampling settings are global.
• If no "RRAs" stanza is defined a default configuration is used.
• For historic reasons all values are specified in intervals of 15 seconds.

Example: Default settings in Ganglia

RRAs "RRA:AVERAGE:0.5:1:240"    \
     "RRA:AVERAGE:0.5:24:240"   \
     "RRA:AVERAGE:0.5:168:240"  \
     "RRA:AVERAGE:0.5:672:240"  \
     "RRA:AVERAGE:0.5:5760:370"

Translation:

• Take 240 samples at 1 × 15 seconds intervals (used for display of hour)
• Take 240 samples at 24 × 15 seconds (= 6 minutes) intervals (used for display of day)
• Take 240 samples at 168 × 15 seconds (= 42 minutes) intervals (used for display of week)
• Take 240 samples at 672 × 15 seconds (= 168 minutes) intervals (used for display of month)
• Take 370 samples at 5760 × 15 seconds (= 24 hours) intervals (used for display of year)

Example: 1-minute sampling for one year

RRAs "RRA:AVERAGE:0.5:4:525600"

Translation:

• Take 525600 samples at 4 × 15 seconds (= 1 minute) intervals
• 525600 = 60 (samples/hour) × 24 (hours) × 365 (days) × 1 (year)

Example: 1-minute sampling for 6 months, 5-minute sampling for 2 years

RRAs "RRA:AVERAGE:0.5:4:259200"  \
     "RRA:AVERAGE:0.5:20:210240"

Translation:

• Take 259200 samples at every 4 × 15 seconds (= 1 minute) intervals
• 259200 = 60 (samples/hour) × 24 (hours) × 30 (days) × 6 (months)
• Take 210240 samples at every 20 × 15 seconds (= 5 minutes) intervals
• 210240 = 12 (samples/hour) × 24 (hours) × 365 (days) × 2 (years)

Example: 15-second sampling for 1 day, 1-minute sampling for 2 months, 10-minute sampling for 1 year

RRAs "RRA:AVERAGE:0.5:1:5760"   \
     "RRA:AVERAGE:0.5:4:86400"  \
     "RRA:AVERAGE:0.5:40:52560"

Translation:

• Take 5760 samples at every 1 × 15 seconds intervals
• 5760 = 4 (samples/minute) 60 (samples/hour) × 24 (hours)
• Take 86400 samples at every 4 × 15 seconds (= 1 minute) intervals
• 86400 = 60 (samples/hour) × 24 (hours) × 30 (days) × 2 (months)
• Take 52560 samples at every 40 × 15 seconds (= 10 minutes) intervals
• 52560 = 6 (samples/hour) × 24 (hours) × 365 (days) × 1 (year)

Example: 1-minute sampling for 2 months, 5-minute sampling for 6 months, 15-minute sampling for 3 years

RRAs "RRA:AVERAGE:0.5:4:86400"   \
     "RRA:AVERAGE:0.5:20:51840"  \
     "RRA:AVERAGE:0.5:60:105120"

Translation:

• Take 86400 samples at every 4 × 15 seconds (= 1 minute) intervals
• 86400 = 60 (samples/hour) × 24 (hours) × 30 (days) × 2 (months)
• Take 210240 samples at every 20 × 15 seconds (= 5 minutes) intervals
• 51840 = 12 (samples/hour) × 24 (hours) × 30 (days) × 6 (month)
• Take 105120 samples at every 60 × 15 seconds (= 15 minutes) intervals
• 105120 = 4 (samples/hour) × 24 (hours) × 365 (days) × 3 (years)