external rrd create and update

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noname
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Re: external rrd create and update

Post by noname »

>> so is it mean I increase the heartbeat will fix that problem?

Probably yes -- as far as you update rrd within the time of heartbeat.

FYI: You can modify heartbeat value by rrdtune without re-creating rrd file.
Last edited by noname on Tue Jun 21, 2011 12:30 am, edited 1 time in total.
chefchanyu
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Posts: 153
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Re: external rrd create and update

Post by chefchanyu »

no looking good.
because they taking last valid input to replace with "NaN".
is there possible way replace "NaN" with "0" rather than last valid input?
Last edited by chefchanyu on Tue Jun 21, 2011 12:50 am, edited 1 time in total.
noname
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Re: external rrd create and update

Post by noname »

chefchanyu wrote:because they taking last valid input to replace with "NaN".
Sorry I can't understand what this means.

Please indicate, "What value you updated (last and previous last)" and "When you updated that value (last and previos last)".
chefchanyu
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Joined: Wed Aug 25, 2010 11:07 pm

Re: external rrd create and update

Post by chefchanyu »

Code: Select all

20110615030017 1
: 15 seconds
20110615030032 1
the 15 seconds has no input it mean = "0". when i change the heartbeat to 60, the result is like this.

Code: Select all

<!-- 2011-06-15 03:00:17 EST / 1308070817 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:18 EST / 1308070818 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:19 EST / 1308070819 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:20 EST / 1308070820 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:21 EST / 1308070821 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:22 EST / 1308070822 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:23 EST / 1308070823 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:24 EST / 1308070824 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:25 EST / 1308070825 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:26 EST / 1308070826 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:27 EST / 1308070827 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:28 EST / 1308070828 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:29 EST / 1308070829 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:30 EST / 1308070830 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:31 EST / 1308070831 --> <row><v> 1.0000000000e+00 </v></row>
                        <!-- 2011-06-15 03:00:32 EST / 1308070832 --> <row><v> 1.0000000000e+00 </v></row>
noname
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Re: external rrd create and update

Post by noname »

Thanks, I've understood about your situations.
Unfortunately(?), it seems that this depends on RRDtool behavior.
http://oss.oetiker.ch/rrdtool/doc/rrdcreate.en.html

The HEARTBEAT and the STEP
...
The "heartbeat" can be short (unusual) or long (typical) relative to the "step" interval between PDPs.
A short "heartbeat" means you require multiple samples per PDP, and if you don't get them mark the PDP unknown.
A long heartbeat can span multiple "steps", which means it is acceptable to have multiple PDPs calculated from a single sample.
An extreme example of this might be a "step" of 5 minutes and a "heartbeat" of one day, in which case a single sample every day will result in all the PDPs for that entire day period being set to the same average rate.
Then, if you want to avoid storing valid value when no data comes, choose between the below two.
(Is there another choice?)

(A) Reduce heartbeat (2 or 3 or else). But you will lost more "valid" data. (as you faced)
(B) Use this heartbeat (60secs), and supplement by NaN (or 0) during every seconds which no data comes. (as you mentioned)

---

BTW, I misunderstood in the previous post.
noname wrote:>> don't know why start print out form 2008 to 2011.

Probably you specified that timestamp (3 years ago) by "--start" option when creating this rrd.
It seems that this relates "--start" option & rows (94608000) in RRA definitions. Sorry.
(I'm not sure in detail)
chefchanyu
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Posts: 153
Joined: Wed Aug 25, 2010 11:07 pm

Re: external rrd create and update

Post by chefchanyu »

Thanks noname. I had learn lot from you.
I think only way fix this problem is change the Perl script.
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