srsieve/sr2sieve enhancements

[axn]

Originally Posted by Citrix

Looking at above code from sr1sieve. Can somebody point me to math behind this code. Thanks.

It is a consequence of Merten's theorem (https://en.wikipedia.org/wiki/Mertens%27_theorems - see third theorem)

[lukerichards]

I have had srsieve running on my laptop for the past few weeks.

I have 4 instances of it open in 4 seperate Windows PowerShells. All writing to seperate .out files every 10 minutes.

I also have a python script running which reads all 4 .out files every 10 minutes, counts how many entries are present in ALL 4 lists and records how many terms there are remaining.

The python script also outputs the average time taken, in minutes, for each term eliminated over the past 5 hours.

So here's the odd thing...

Every night I lock my computer and go to bed, leaving srsieve running. I wake up, unlock the computer and check the python shell output.

This morning shows that the srsieve had been eliminating 1 term every 27 minutes on average over the past 5 hours. Within 2.5 hours of actively using the laptop for work, this average has dropped to 18 minutes.

This is a recurring pattern... I wake up in the morning and srsieve has slowed down considerably overnight. Srsieve picks up again when I unlock the computer and start using it for other things. It has followed the same pattern every morning since I first noticed it a week ago.

This is possibly *not* an srsieve specific query - it might be more likely to do with how Windows runs while locked.

But does anyone know what's going on here?

[rogue]

Originally Posted by lukerichards

But does anyone know what's going on here?

What are your Power options? Does Windows or your hard drive "go to sleep" if you are not actively using?

[lukerichards]

Originally Posted by rogue

What are your Power options? Does Windows or your hard drive "go to sleep" if you are not actively using?

Nope... power settings attached in screenshot form. Nothing sleeps ever, not even while I'm sleeping.

[rogue]

When locked is a screen saver running? Can you take a look to see if something else is running that is stealing CPU cycles, e.g. malware?

[henryzz]

Is the CPU clock lowering when locked?

[lukerichards]

Originally Posted by rogue

When locked is a screen saver running? Can you take a look to see if something else is running that is stealing CPU cycles, e.g. malware?

It's a work computer (which our Ts and Cs do allow us to use for personal projects if they don't put any strain on the network infrastructure at work) so there are lots of things running which I wouldn't normally have running on my own computer.

Scanning down the active processes list, I notice a few things that might potentially update/sync/run at night/downtime or something similar not least various incarnations nof Sophos virus scanning/security services.

Tonight I'll have a look at disabling anything non-critical and see how it fares by the morning.

[lukerichards]

Originally Posted by henryzz

Is the CPU clock lowering when locked?

How would I check?

[kruoli]

Originally Posted by lukerichards

How would I check?

You could run HWInfo. This program is able to log the current frequency of your processor over night. It can also log a ton of more things, maybe this is helpful in your case.

[storm5510]

Originally Posted by rogue

When locked is a screen saver running?

George Woltman, a.k.a. "Prime95", wrote something about screen savers. He indicated to never use one which would require mathematical calculations when running. The majority of them do. He recommends just a blank screen. Windows has had this for many years. I know Ubuntu Linux has it as well.

[rogue]

The only change from 1.1.4 is to replace the error for "all terms divisible by 2" with a warning.