616 reputation
33
bio website redhardsupra.blogspot.com
location Laurel, MD
age 37
visits member for 4 years, 3 months
seen 2 days ago

Aug
18
awarded  Yearling
Jul
12
comment What Linux tool will tell me if all the mounted disks share roughly the same bandwidth?
iostat -x -m 5 is very helpful in diagnosing if you have one disk that' under-performing. -x gives you extra details about each disk, and you get to see each disk separately. Extra useful when you got software RAID, as you can look at your array as parts (disks), and as the whole (the RAID device).
Jul
12
comment Pros and cons of software Parity-RAID (e.g. RAID5)
That'd do it, but at that moment you're paying more than a decent controller in the first place ;) Also, speed goes up, but the reliability goes down, because most SSD's die very very quickly.
Jul
11
answered How to process/pipe TCPDUMPs output in realtime
Jul
11
answered Verify that /etc/passwd has correct number of fields on each line?
Jul
11
answered Pros and cons of software Parity-RAID (e.g. RAID5)
Jul
8
awarded  Commentator
Jul
8
comment Howto create a permanent client connection with netcat?
Take a look at socat, it's a netcat replacement that has a built-in functionality to respawn pipes after they've finished.
Jun
7
comment How to limit resource usage to save CPU+RAM for a certain process?
When linux runs out of memory, it starts killing off processes to reclaim memory. You might be seeing OOM in action (out of memory killer). I don't know why would it decide to kill your sshd consistently though. Have you ever seen sshd actually leak (grow in size) horribly, before it blows up, or does it work fine one moment and is dead the next?
Jun
7
comment How to limit resource usage to save CPU+RAM for a certain process?
Sshd should not be blowing up like that, it's normally a very well behaving daemon. Make sure it's updated to the latest/greatest. What are you doing with it? Are you piping massive data through it?
May
17
comment What is the difference between .a and .so file?
You can also run ldd on .so's, and it will show you what other libraries it uses. Static will return with a message saying it's not a dynamic library.
May
16
answered nmap output: what does “uptime” mean?
May
15
answered Debian Lenny on Asus sabertooth X58 won't detect hard drive
May
13
comment GPGPU/CUDA in KVM or Xen
I know it's not direct answer, but I've tried using a 200 series Nvidia with ESXi 4.1 and got nowhere. Even with the passthrough set up to the correct PCI addresses, the guests were not able to access the devices with the access CUDA programs want.
May
10
comment Problem on Linux NAND Root Filesystem
How old is your kernel? I've seen some very odd behaviours from JFFS2 on older kernels.
May
6
comment How to cache or otherwise speed up `du` summaries?
Counting up file sizes for du is slow because you have to access metadata of a potentially large number of files, scattered around the disk. If you run updatedb aggressively, the metadata for all the files is forced to be stored in RAM. The next time you run any other metadata-heavy operation, instead of doing thousands of seeks across the disks, you use the cache. Normally you have a small chance of having that particular portion of the tree's metadata cached. With my 'metadata cache priming' it's highly probable that the data you want is freshly cached. No physical seeks == FAST.
May
5
comment What are your favorite command line features or tricks?
This is also super useful for comm as it takes files only, but in a lot of cases that's a waste of inodes.
May
5
answered How to cache or otherwise speed up `du` summaries?
Mar
28
awarded  Teacher
Mar
28
answered Multiline pattern match using sed, awk or grep