Sam Howard wrote: > > When I dump the database, with a steptime=86400 (1 day), I notice that it > chooses 20:00 (8:pm) as the time, even though I am running the create script > at 16:00 (4:pm). As seen by:
It really chooses 00:00 UTC... It represents it as 20:00 EDT. > But, here's where it get's weird (and maybe why my values are getting > "helped")...after a few days, in the database, the time *changes*: > > <!-- 1997-10-25 20:00:00 EDT --> <row><v> NaN </v><v> NaN </v></row> > <!-- 1997-10-26 19:00:00 EST --> <row><v> NaN </v><v> NaN </v></row> Again: 20:00 EDT ---> 00:00 UTC 19:00 EST ---> 00:00 UTC (I'm now guessing that EDT is EST with daylight saving applied). > It goes back and forth every so many months!! Let me guess: april and october, and every time on a sunday. > I notice that if I reduce the steptime, to anything other than 3600 or 7200, > that I get time fluctuations... You should get problems with 7200. Everything under 3600, provided that 3600 modulo time step is zero, is okay. > I hate to waste so many records (24 per day) just to work around this... Just don't look at it as wasting space. If you have a good reason to do so, do so. However, for this particular purpose you can say *you* are wasting space if *you* choose to use 3600 seconds time steps. I guess you're only interested in the yearly archive and therefore want only update once every day. Do this at 00:00 UTC and there's no problem. For any moment in time, you can find the RRDtool boundary by doing an integer division of the current time, then multiplying the outcome with the same number. [EMAIL PROTECTED] ~]$ date;date +%s Mon Sep 25 22:36:04 MET DST 2000 969914165 [EMAIL PROTECTED] ~]$ bc bc 1.03 (Nov 2, 1994) Copyright (C) 1991, 1992, 1993, 1994 Free Software Foundation, Inc. This is free software with ABSOLUTELY NO WARRANTY. For details type `warranty'. 969914165/86400 11225 .*86400 969840000 [EMAIL PROTECTED] ~]$ perl -e 'use POSIX;print ctime(969840000);' Mon Sep 25 02:00:00 2000 This is correct. Our time is one hour ahead of UTC. Daylight savings account for the other hour. You can update the RRDtool database you currently have if you make sure that you (a) update on or after 00:00 UTC and (b) perform some math on the current time. Warning: I'm just starting to learn perl. Others can probably write a better program to do this but until they share it, here's mine: perl -e '$x=time();print $x-($x%86400)."\n";' regards, -- __________________________________________________________________ / [EMAIL PROTECTED] [EMAIL PROTECTED] \ | work private | | My employer is capable of speaking therefore I speak only for myself | +----------------------------------------------------------------------+ | Technical questions sent directly to me will be nuked. Use the list. | +----------------------------------------------------------------------+ | http://faq.mrtg.org/ | | http://rrdtool.eu.org --> tutorial | +----------------------------------------------------------------------+ -- Unsubscribe mailto:[EMAIL PROTECTED] Help mailto:[EMAIL PROTECTED] Archive http://www.ee.ethz.ch/~slist/rrd-users WebAdmin http://www.ee.ethz.ch/~slist/lsg2.cgi
