mersenneforum.org  

Go Back   mersenneforum.org > Great Internet Mersenne Prime Search > PrimeNet

Reply
 
Thread Tools
Old 2003-03-12, 17:06   #1
eepiccolo
 
eepiccolo's Avatar
 
Dec 2002
Frederick County, MD

37010 Posts
Default Truncation of PrimeNet Summary Report

OK, try going to the PrimeNet summary report at http://www.mersenne.org/primenet/summary.txt. Chances are, you would see a report truncated around 18000000. The report has behaved like this for as long as I have been in the project (5 months), and only occasionally when you look at the summary will you get a full report. The reason I bring this up now is that the first-time test are in the 18,000,000 range now, whereas before, the truncated report was not such a big issue.
So, is there any way that the report can be fixed to behave properly and consistently?
Oh, and another issue is that the report claims to be updated hourly, but right now, it is 1705 UTC, and the report says it was lat updated at 1200 UTC.

Tim (eepiccolo)
eepiccolo is offline   Reply With Quote
Old 2003-03-12, 23:38   #2
jeff8765
 
jeff8765's Avatar
 
Aug 2002
A Dyson Sphere

1111112 Posts
Default

The report used to update every hour and go to the full length within 15 minutes. Around 6 months ago it started taking about 6 hours and being complete only for about the last half hour. I don't know why it did that though.
jeff8765 is offline   Reply With Quote
Old 2003-03-13, 01:55   #3
NickGlover
 
NickGlover's Avatar
 
Aug 2002
Richland, WA

22×3×11 Posts
Default

Quote:
Originally Posted by jeff8765
The report used to update every hour and go to the full length within 15 minutes. Around 6 months ago it started taking about 6 hours and being complete only for about the last half hour. I don't know why it did that though.
Also, at the same time that it started taking really long to generate, it started showing a bunch of lines like

[code:1]******** ******** 1[/code:1]

at the very end of the report. I'm guessing this issue is related to the really long generation time.
NickGlover is offline   Reply With Quote
Old 2003-03-13, 04:53   #4
cheesehead
 
cheesehead's Avatar
 
"Richard B. Woods"
Aug 2002
Wisconsin USA

22×3×641 Posts
Default

Possible scenario: The report generator is failing to find, or to understand, some end-of-data indicator for the PrimeNet data base, and is continuing to process junk past the last valid data for quite a while. Once in a while the junk is close enough to valid data format for the program to interpret as an interval with bounds over 10^8, so it tries to spit out another report line. The language in which the generator is written handles integer field overflow by substituting asterisks instead of showing a truncated value or pushing the rest of the record to the right to accommodate outputting the entire overflowing value.

That behavior started only a few months ago because only then did data values exceed some limit below which the generator processed correctly.

Prediction: It will continue until someone fixes the report generator bug.

Advice: Until bug fix, set an alarm clock for about 5.5 hours past the time shown in the report heading to remind you to go back to see the complete report during the window of display completeness, which is from then until the end of that clock hour. That 5.5 hour interval will steadily increase over time, and the corresponding duration of the completeness window will decrease, until reaching 6 hours, at which time the completeness window will jump back to almost one hour then decrease again. In the absence of a bug fix, the interval will continue to 7, 8, 9 ... hours past report heading time, unless another program limitation or bug causes an abort at some point.
cheesehead is offline   Reply With Quote
Old 2003-03-13, 06:38   #5
trif
 
trif's Avatar
 
Aug 2002

3128 Posts
Default

Several months before the report started having this multi-hour behavior, some members of Team Prime Rib asked George for some whopper exponents, up in the 79.2M range (what can I say, these guys are crazy, gotta love 'em, 2 months just to do the P-1). George put them in Primenet and let them pick them up through doing a manual connect. When that happened the report went from taking 5 minutes to complete to taking about 15 minutes. Since there were only a few added exponents, it was obvious that the report program was doing some kind of linear query on possibly every prime exponent between 0 and the upper limit of what was in Primenet, and thus having to compute and look up everything between the 33M's that were the highest and the 79M's that were the new highest, and this was delaying the report.

So perhaps something is corrupted and Primenet thinks the upper bound is somewhere in the several hundred millions or billions. If Primenet has to test every exponent for primality, that becomes more and more expensive the higher you get. Perhaps someone manually stuck some really big exponents in their worktodo and did a connect and this screwed Primenet up.

And just to give eepiccolo a teasing poke, it's been an issue for those of us who work factoring for quite some time. ;) I just deal by estimating that five and a half hours, as cheesehead details. So I get a full report four times a day.
trif is offline   Reply With Quote
Old 2003-03-13, 13:21   #6
eepiccolo
 
eepiccolo's Avatar
 
Dec 2002
Frederick County, MD

1011100102 Posts
Default

Quote:
Originally Posted by trif
And just to give eepiccolo a teasing poke, it's been an issue for those of us who work factoring for quite some time. ;) I just deal by estimating that five and a half hours, as cheesehead details. So I get a full report four times a day.
Whoops ops: . Sorry about that factorers (Is that a word? :( ). And thanks for the four report a day info; I was unaware of that.
eepiccolo is offline   Reply With Quote
Old 2003-03-13, 13:32   #7
norbert
 
Aug 2002

3·7 Posts
Default

I have this line in my crontab:
[code:1]
50 * * * * cd /home/norbert/bin; ./crday
[/code:1]

where crday is a perl script that contains the following lines (among others):

[code:1]
$fn= "prime/status/summary";
$url="'http://mersenne.org/primenet/summary.txt'";
open FILE, "/usr/bin/lynx -source $url |";
@lines=<FILE>;
close FILE;

if (grep /33500000/,@lines)
{
open OUT,">$fn";
print OUT @lines;
close OUT;
}
[/code:1]
norbert is offline   Reply With Quote
Old 2003-03-26, 12:24   #8
tha
 
tha's Avatar
 
Dec 2002

11×73 Posts
Default

Quote:
Originally Posted by cheesehead
The language in which the generator is written handles integer field overflow by substituting asterisks instead of showing a truncated value or pushing the rest of the record to the right to accommodate outputting the entire overflowing value.
I noticed that the number of lines went up in the past weekend, after the long outage.

Also, this suggest that the server could be fixed with relative little work, right?
tha is offline   Reply With Quote
Old 2003-03-26, 21:10   #9
tha
 
tha's Avatar
 
Dec 2002

11·73 Posts
Default

Given the fact that it is frequent down now, just after the sudden increase in these lines, suggests that the server breaking down once or twice a day will continue until the root cause has been eliminated.

YotN,

Henk.
tha is offline   Reply With Quote
Old 2003-03-26, 22:00   #10
NickGlover
 
NickGlover's Avatar
 
Aug 2002
Richland, WA

22·3·11 Posts
Default

Quote:
Originally Posted by tha
I noticed that the number of lines went up in the past weekend, after the long outage.
Actually, the number of messed up lines has been steadily going down.

Some samples from my saved archive of summary.txt files:
31-Jan-03: 36
14-Feb-03: 33
21-Feb-03: 27
01-Mar-03: 18
14-Mar-03: 14
20-Mar-03: 13
21-Mar-03: 12
25-Mar-03: 12

I'm guessing the extremely high exponents are expiring, and once they all expire, hopefully the summary will start taking 20 minutes or less again.
NickGlover is offline   Reply With Quote
Old 2003-03-27, 08:43   #11
tha
 
tha's Avatar
 
Dec 2002

11×73 Posts
Default

Quote:
Originally Posted by NickGlover
Actually, the number of messed up lines has been steadily going down.
Hmm, yesterday, I was pretty sure a saw a screen full of them, today I can't find that many. The last line however stops halfway, the "1" is missing suggesting the report is not fully printed before a new starts.
tha is offline   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Machines Missing from Primenet Summary edron1011 PrimeNet 2 2008-11-17 19:16
PrimeNet Report ZFR PrimeNet 4 2008-02-13 12:14
Asterisk in Primenet Account Report jinydu PrimeNet 5 2006-10-30 02:55
Core 2 Duo in primenet report tha PrimeNet 3 2006-08-06 22:19
Once again: How to report offline-work to primenet? Unregistered PrimeNet 19 2004-01-22 23:41

All times are UTC. The time now is 12:08.

Tue Jan 26 12:08:19 UTC 2021 up 54 days, 8:19, 0 users, load averages: 3.20, 2.67, 2.66

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.

This forum has received and complied with 0 (zero) government requests for information.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation.
A copy of the license is included in the FAQ.