380 reputation
17
bio website liori.jogger.pl
location Wroclaw, Poland
age 28
visits member for 4 years, 11 months
seen Jun 8 at 16:35

Jul
2
awarded  Curious
Oct
21
comment Grep-ing gzipped files
Which is how zgrep is actually implemented, as it is just a shell script (with some additional stuff to handle arguments and report errors properly).
Sep
14
comment Is there any such error logged by CentOS somewhere that can conclusively reveal “it is now time to pay for ECC”
This is far from a full answer, but if you're running Redis, it has a built-in memory test (antirez.com/news/43). This is the only instance I know of server software that does that, though.
Jun
11
comment Automatically suspend/hibernate a process when too much memory taken
I don't understand your suggestion about sched_min_granularity_ns—could you explain how does it interact with swapping?
Jun
11
comment Automatically suspend/hibernate a process when too much memory taken
The problem is mostly memory-bound, and I want to try using all the memory available. So, in my case I won't be able to just let a process go faster, because there won't be enough memory for that—and swapping kills all performance. I prefer to pause one of the processes and restart it when some other process finish. That probably also explains that I wasn't going to do a round-robin. CPU time is not an issue here—tasks are single-threaded, so in best case I could run 8 of them on each machine at the same time without them slowing down. But I can't due to memory problems.
Jun
11
comment Automatically suspend/hibernate a process when too much memory taken
Thank you for thorough answer. Yes, I know about checkpointing and related issues—actually I am happy with just suspending the process and letting it go into swap. Also, my tasks do not communicate with the world much, so the existing checkpointing solutions (with their issues regarding signals) would be fine too. I just didn't want to focus on that part in my question. I did not know that I can ask cgroups to pause process instead of killing it on OOM—that will probably be good enough for me. And to answer your other suggestions…
Jun
11
comment Automatically suspend/hibernate a process when too much memory taken
VSZ measures total allocated virtual memory, which includes “inactive” memory (pages which were never written to). In my case there can be lots of such pages, and the inactive pages do not actually take physical memory.
Jun
10
revised Automatically suspend/hibernate a process when too much memory taken
added 5 characters in body
Jun
10
comment Automatically suspend/hibernate a process when too much memory taken
@MichaelHampton: the tasks test different variations of a certain algorithm, and one of the goals is actually to prepare a model for predicting resource usage… so it is possible, we just don't have enough data yet.
Jun
10
asked Automatically suspend/hibernate a process when too much memory taken
Jan
30
accepted Solaris' `killall`
Dec
26
comment Heavy disk write on a Debian VPS gives “ata1: lost interrupt (Status 0x50)”
I just had a problem which seems similar to yours, and also on Hetzner's VQ12, except that I run a hdparm -t test (which completed successfully) and the problem showed up few hours later. It indeed looks strange, and I plan to contact their support. May I ask whether you resolved the problem?
Nov
25
accepted Discovering PHP apps
Nov
25
accepted Backup process flushes disk cache
Nov
25
asked Solaris' `killall`
Sep
16
comment Locating large files (> 100 MB) in /home/ for 'cleaning'
And ncdu has the advantage of being interactive.
Sep
16
answered Locating large files (> 100 MB) in /home/ for 'cleaning'
Apr
30
awarded  Scholar
Apr
30
accepted Non-deterministic behavior of `sudo`
Apr
22
revised Force process pages to get unswapped
typo