So basically, my logs look like this:

8/10/2015 2:56:14 PM | GPUGRID | [checkpoint] result e2s1_e1s14f430 GERARD_FXCXCL12_LIG_15353472-0-1-RND8208_1 checkpointed
8/10/2015 2:56:30 PM | GPUGRID | [checkpoint] result e2s1_e1s14f430-GERARD_FXCXCL12_LIG_15353472-0-1-RND8208_1 checkpointed
8/10/2015 2:56:47 PM | GPUGRID | [checkpoint] result e2s1_e1s14f430-GERARD_FXCXCL12_LIG_15353472-0-1-RND8208_1 checkpointed
8/10/2015 2:57:03 PM | GPUGRID | [checkpoint] result e2s1_e1s14f430-GERARD_FXCXCL12_LIG_15353472-0-1-RND8208_1 checkpointed

Im wondering if this intended behavior? Checkpoints every 15 seconds? I don't baby my SSDs, haven't really ever paid attention to what does disk writes when, but I get a little nervous when I see GPUgrid writing 120Gb worth or data every 24 hours. That's a lot.

I didn't even believe the numbers I was seeing in Resource Monitor at first, but it showed restart.coor, restart.vel and restart.idx in the GPUgrid directory open and being written to constantly, and BOINC logs backed it up. So I decided to run a day with just WCG, and a day with WCG and GPUgrid and compare S.M.A.R.T. data. I went from 500Mb to 118Gb per day with GPUgrid crunching.

I'm new to BOINC, but I tried adjusting the checkpoint frequency settings and had no affect. Is there perhaps a config file setting? I mean I can always just set up a RAM disk and move on, but I guess the real question is whether this is really the intended behavior or not. That's a lot of thrashing drives out there if it is.

My GERARD_FXCXCL12_LIG have been check-pointing about every 5.5 minutes. I have the minimum checkpoint interval set to 300 seconds (5 minutes) for whatever good that does, using BOINC 7.6.6 x64 (Win7 64-bit). Maybe your version of BOINC needs updating?

But I agree 120 GB per day is too much; I use a write-cache (PrimoCache) to protect the SSDs in those machines, though it was not for GPUGrid but because I run WCG/CEP2 on the CPUs.

Thanks Jim, I am using the latest stable version. That's interesting that you are using the same OS as me, but the development client and not seeing the issue. I will try that out.

I noticed the CEP2 being completely nuts as well, but not due to constant checkpointing. It may be programmed inefficiently (or not, no idea), but this checkpointing business looks like a bug in BOINC or GPUgrid.

Actually I happen to have a CEP2 WU going right now, and it's written 30Gb in the last 30 minutes. Sheesh.

I've checked it on my hosts (with the built in task manager), and I've found that at 50% completion the acemd.847-65.exe app wrote nearly 3.5GB. On a host with a GTX 980 and Windows XP x64 it will write ~23.26GB every day. This much data will not shorten an SSD's lifetime significantly. However the GPUGrid app actually does not checkpoints according to the period set in BOINC manager.

I've checked it on my hosts (with the built in task manager), and I've found that at 50% completion the acemd.847-65.exe app wrote nearly 3.5GB. On a host with a GTX 980 and Windows XP x64 it will write ~23.26GB every day. This much data will not shorten an SSD's lifetime significantly. However the GPUGrid app actually does not checkpoints according to the period set in BOINC manager.

That's interesting, doobedy! I have the same BOINC version as you have and am seeing frequent file changes in a GPU-Grid slot directory as well. In ressource monitor the data rate of the GPU-Grid process is really low, though, never exceeding 100 B/s (watched ~ 1 min).
How do you check how much a process has already written?

MrS

Interesting. Did you actually see checkpoints spaced out 5 minutes in the event log? Are your preferences are set 300 seconds?

I installed 7.6.6 fresh, re-added my proects, and it's still humming along making checkpoints every 15 seconds.

I setup a RAM disk, which I have mixed feelings about. If I lose WUs because of unexpected shutdowns, I'll have to give up on that. I already lost some after upgrading.

I setup a RAM disk, which I have mixed feelings about. If I lose WUs because of unexpected shutdowns, I'll have to give up on that. I already lost some after upgrading.

I keep my BOINC Data directory on a mechanical drive, even though the OS is installed on an SSD.

Whatever is left in my 33-34 GB/day is not influenced by the checkpoint time I set in BOINC. I tried 300 and 180s, each over a whole night and without any WCG CEP2 WUs. The transferred was pretty much the same.

MrS

It helps to have an uninterruptible power supply (UPS), especially in the spring and summer months when lightning can produce brief outages. In my area, they last for only a second or two, but I use UPS on all my machines to bridge the gap. And if the machines are not stable but crash for other reasons, I would attend to that first before putting BOINC data on a ramdisk.

I stream Netflix and play games while BOINC remains at 100% load in the background. It's happily done that for weeks, but not all programs are good neighbors. Lock ups happen.

You can turn on the <checkpoint_debug> flag, in your cc_config.xml file or by changing "Event Log Options" on the user interface, to see the checkpoints happen, per http://boinc.berkeley.edu/wiki/Client_configuration ... and you'll see the lines in the Event Log that the original post shows.

The BOINC checkpoint setting has actually been renamed in the 7.6.x version (not publicly released yet), to better indicate that it is only a request. The setting is now described as "Request tasks to checkpoint at most every x seconds". I have that setting set to 60.

From my experience, GPUGrid ignores that request, at least for most of its task types. Looking at the data, it seems that different GPUGRID task types checkpoint at different intervals -- some as often as every 15 seconds, some as sporadically as every 60 seconds. You can turn on the debug flag to measure it properly, dumping the data into Excel and sorting it to see what you need to see.

I think it'd be nice if GPUGrid did honor the setting.