Marcin

1,272 reputation

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bio	website	redhardsupra.blogspot.com
	location	Charleston, SC
	age	35
visits	member for	3 years, 11 months
	seen	17 hours ago
stats	profile views	196

	1,272 reputation	bio	website	redhardsupra.blogspot.com	visits	member for	3 years, 11 months
158 badges		location	Charleston, SC		seen	17 hours ago

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Apr 11	awarded	Notable Question
Jan 7	comment	Very slow write performance on Debian 6.0 (AMD64) with DMCRYPT/LVM/RAID1 How does the write performance change when you mount it without `sync`?
Dec 20	comment	Linux Experts Riddle: Network output of 10MB/s on 10GB/s NIC When copying files over network pipes, turn off compression, copy a file from a ramdisk to another ramdisk, or something simpler, like stream reading /dev/zero, xfering it, and then dumping it out to /dev/null. When dd'ing, remember to play with block sizes and flags on BOTH sides (especially flags might not be symmetric!). When playing with qperf/iperf/netperf, make sure you're controlling window sizes and TCP congestion algorithms. Watch switch statistics. If not meaningful, connect two boxes directly, see if it changes anything. Install new drivers, especially Intel, both Win and LNX.
Oct 18	comment	Is there a tool that can take partition table information and partition another based on it? `parted` should do it. it can print out partitions in any unit you want, and then more invocations of parted would recreate it step by step.
Oct 10	comment	Putting /etc under source control `etckeeper` is awesome. Two gotchas tho: for backup, you end up pushing the repo somewhere remote. Please use key-based SSH for that, so it gets done securely. Also, what you store in `/etc` can be sensitive (think `/etc/shadow` or any private keys) so make sure that whereever you push the repo to does not have a 'public' webpage, or is being served out through any other unauthenticated means.
Sep 7	comment	Linux software RAID that uses system RAM for write cache Is it per data disk, or disks total? Since it's RAID5, you got N disks in array, but N-1 of data.
Sep 4	comment	ksoftirqd hitting 100% on interface with ixgbe driver Have you tried the newest drivers from Intel's site? I find them to solve a lot of problems, the drivers that come with distros tend to lag behind quite a bit, which causes issues with newer hardware.
Aug 22	comment	How to copy a large LVM volume (14TB) from one server to another? How does a tar pipe handle open/changing files, in comparison to let's say rsync? 14TB move is obviously not going to be an atomic operation ;)
Aug 16	comment	FreeNAS Setup (hardware & volume setup) ZFS loves RAM, that's why he's going for it.
Aug 15	revised	Creating tmpfs file system in xen server to store VM experiment added
Aug 15	answered	Creating tmpfs file system in xen server to store VM
Aug 2	comment	Improving TCP performance over a network with small packet loss I've had good results with `hybla`, give that a try.
Jul 19	comment	How do I parse a log file for one hour with a simple shell script? Rotate your logs hourly, run analysis on the individual log, which happen to be hour long.
Jun 25	comment	Resize base XenServer 6.0 partition I figured it wasn't that important, since you're screwing with partitions on it ;) in that case, if you have enough space you can yum install gcc and compile gdisk or parted in Dom0.
Jun 25	answered	Resize base XenServer 6.0 partition
May 27	awarded	Yearling
Mar 23	comment	Grepping through the results of apachectl -S What you pipe to grep is stdout, are you sure that apachectl -S is dumping to stdout, or stderr? Redirect stderr to stdout, grep on that.
Mar 9	comment	Anything Close to an NSA Guide for Securing RHEL 6 I don't think RHEL6 have been approved for anything gov/mil operations yet, so no STIGs or SNACs have been released.
Mar 8	comment	Faster MySQL DB pull from remote machine into local machine Good point on using ssh's internal ability to gzip. However, in the modern times, it's advisable to use things like pbzip2, as it can take advantage of (sometimes significant) number of cores. The traditional bzip2 is rather slow, but pbzip2 on a modern box will amaze you.
Mar 6	comment	monitor IO to tmpfs partition? Running PV adds its own bottlenecks, usually invisible at disk speeds, but they will be significant at RAM speeds. Beware.