What is NumberFields@home?

Join NumberFields@home

User of the Day

User profile Profile Alan E. Monroe
HR Professional from Illinois, USA. I have been crunching off and on since 2000 for the greater good and advancement of science.

News

Server Maintenance This Friday.
We will be taking the server down for several hours on Friday, Feb 2nd, starting around 9am (AZ time).

This is to replace the failing hard drive in our RAID.
30 Jan 2018, 1:21:26 UTC · Discuss


2017 year in review
Although the list does not look impressive, much was accomplished in 2017. The sub-searches that were completed were some of the longest so far. In summary:
1. The search over Q(sqrt(2)) (subfield 3 of 7) completed several more tiers of the search. There are about 9 tiers left to go.
2. The search over Q(sqrt(-2)) (subfield 4 of 7) filled in a bunch more rows. This one has 7 tiers left to go.

Here are the goals for the new year:
1. Develop a GPU app. I have enlisted the help of a fellow user for this. This is a lofty goal and it could be many months before the GPU app is available. This app will be critical in completing the search over Q(sqrt(2)).
2. Complete the search over Q(sqrt(-2)).
3. Start the search over Q(sqrt(-5)) (subfield 5 of 7).
13 Jan 2018, 0:14:21 UTC · Discuss


Database crash
We had a database crash. We are working hard to get it fixed.
5 Jan 2018, 1:19:20 UTC · Discuss


Minor server overload problems
Over the last couple days we have been having some overload problems on the server. To help reduce the server load I temporarily disabled the batch_status and server_status cron jobs. I will be manually generating those about once a day. Sorry for the inconvenience. I also reduced the "max_wus_in_progress" from 24 to 6, so you may see fewer WUs in your job queues.

For those who are interested in the cause of the overload, it was a combination of things:
1. One of the drives in our RAID is failing, causing HD performance issues. We are working to get this fixed.
2. There were 10k+ WUs that all timed out at about the same time. The server then proceeds to generate new results for all these, causing a backlog. This is the reason for reducing max_wus_in_progress.
3. The transitioner had a DB timout which caused it to crash, increasing the backlog further.
4. Not understanding why WUs were not transitioning, I stupidly ran the "transition_all" admin script since it said this would "unstick" jobs. Big mistake - this script changed the transition time of all 600k WUs in the DB, forcing the transitioner to now reprocess every WU. That only made the backlog worse.

The good news is the server is almost caught up with the backlog. I will keep you posted.
30 Dec 2017, 17:55:35 UTC · Discuss


New subfield search
As you may have noticed, the search over ℚ(√2) (subfield 3) has started to slow down and waiting for results is like watching paint dry. At the current rate it will probably take over 10 years to finish that search. In the interest of making progress, I have decided to start the search over subfield ℚ(√-2). This is the 4th of 7 subfields for the set {2,5}. We will continue to process subfield 3 in parallel, but at least we will be able to maintain progress on other subfields for the overall goal of this project.

The hope is that I can find time this year to develop a GPU app that will help to speed up the search. Of course I've been saying this for years...
4 Mar 2017, 17:03:58 UTC · Discuss


... more

News is available as an RSS feed   RSS


Main page · Your account · Message boards


Copyright © 2018 Arizona State University