Environment: 4-node Cluster w/8.1.1 and OCUM 5.1 in cluster mode
I am tring to create useful summarized performance data by extracting perf data with the dfm perf data retrieve command. All the data is on 5-minute polling interval as fixed in 5.1 for cluster mode. I would like to create output that is for each hour. I can do that by adding a -s 3600 option on the command line. However, the -s description describes what the option does saying "the last sample in each of those regionss will be displayed" and that matches what I've been seeing (examples below). I find that (the "last sample in period) as useless. Why would I want to report on just what happened in the last 5 minute period of an hour? (or pick your favorite -s value)?
I might want the max of a value in the hour, or the average or mean of a value in the hour, but I'm struggling to think of any case where "last sample" would be useful. I'm attempting to reduce that amount of data for a week from 2016 individual samples (every 5 minutes over 7 days) to more like 288 values (24x7).
So started testing the -m and -S options. It appears the combination of -m mean and -S step returns what I'd like. However I'd really like to obtain mean and max on the same table extract. It looks like I have to do separate dfm perf data retrieve commands to get first mean, then max, right?
Also, I do not understand this description of -S. What do simple, step and rolling return.
-S For computing on fixed size data, this defines the method to advance
the chunks of data. Valid values are simple, step and rolling. Default
value is simple. Valid only when a statistical-method is specified.
Simple and step methods are available for all statistical methods.
Rolling is valid only for mean statistical method.
My questions: Could someone:
- Confirm my thinking that -s 3600 -m mean -S step is returning the mean (or average) value of all samples within the hour (3600 second sample window)
- Provide a better explaination of -S options and examples of when I might use each
=== here is an example to illustrate my questions. This is looking at one counter (cpu_busy) over a 3 hour period from 1am to 4am. ====
dfmc-atx$ dfm perf data retrieve -x timeindexed -o atxcluster01-04 -C system:cpu_busy -b "2013-03-04 01:00:00" -e "2013-03-04 04:00:00" # raw data over 3 hours
Timestamp cpu_busy
2013-03-04 01:09:20 98.843
2013-03-04 01:14:21 99.100
2013-03-04 01:19:20 96.549
2013-03-04 01:24:20 89.707
2013-03-04 01:29:20 90.713
2013-03-04 01:34:20 95.387
2013-03-04 01:39:20 90.508
2013-03-04 01:44:21 63.908
2013-03-04 01:49:20 73.308
2013-03-04 01:54:21 72.283
2013-03-04 01:59:20 73.046
2013-03-04 02:04:20 87.818
2013-03-04 02:09:20 95.400
2013-03-04 02:14:20 94.339
2013-03-04 02:19:21 79.851
2013-03-04 02:24:21 96.548
2013-03-04 02:29:20 99.237
2013-03-04 02:34:21 85.608
2013-03-04 02:39:20 96.100
2013-03-04 02:44:21 86.167
2013-03-04 02:49:21 72.928
2013-03-04 02:54:21 93.406
2013-03-04 02:59:20 78.812
2013-03-04 03:04:21 88.506
2013-03-04 03:09:20 98.307
2013-03-04 03:14:21 97.081
2013-03-04 03:19:20 96.002
2013-03-04 03:24:21 89.469
2013-03-04 03:29:20 92.037
2013-03-04 03:34:21 90.465
2013-03-04 03:39:21 89.942
2013-03-04 03:44:20 78.060
2013-03-04 03:49:20 89.095
2013-03-04 03:54:21 95.153
2013-03-04 03:59:20 86.885
dfmc-atx$ dfm perf data retrieve -x timeindexed -o atxcluster01-04 -C system:cpu_busy -b "2013-03-04 01:00:00" -e "2013-03-04 04:00:00" -s 3600 # sample rate 1 hour (shows last sample)
Timestamp cpu_busy
2013-03-04 02:09:20 95.400
2013-03-04 03:09:20 98.307
2013-03-04 03:59:20 86.885
dfmc-atx$ dfm perf data retrieve -x timeindexed -o atxcluster01-04 -C system:cpu_busy -b "2013-03-04 01:00:00" -e "2013-03-04 04:00:00" -s 3600 -m mean -S step # mean for each hour
Timestamp cpu_busy cpu_busy (mean)
2013-03-04 02:09:20 95.400 86.659
2013-03-04 03:09:20 98.307 89.151
2013-03-04 03:59:20 86.885 90.419 <= I added up the last 10 values and divided by 10 and get 90.419
dfmc-atx$
