326 reputation
18
bio website blog.bitratchet.com
location United States
age 41
visits member for 4 years, 9 months
seen 2 days ago

Jed has maintained an all-weather bicycle commuting lifestyle, and is approaching his first ten thousand miles on his bike. Having started is IT career in 1994, he is now a Java programmer in Ferndale, WA.


2d
awarded  Caucus
May
24
comment UDP bandwidth calculation based on packet size, request rate and latency
Your actual bandwidth will fluctuate a bit of course. Are you collecting this data in a predictable network environment? Do you have bandwidth limits for your equipment? For instance, you could be monitoring raspberry-pi data on a 100Mbps switch. If your traffic has to cross routers, you also want to include jitter for the router.
May
24
comment Hanging after establishing SSH connection
Do you have webmin or a c-panel like web administration utility installed? That would be your next best hope. Did have Xrdp or VNC running on it? Those are unlikely but possible.
May
24
comment Hanging after establishing SSH connection
did you make a snapshot of your server? I would halt the instance and start up from a previous snapshot. Highly likely is that your instance ran out of disk space.
May
24
comment UDP bandwidth calculation based on packet size, request rate and latency
I think you've got it. You could either write a scripts to model it and measure the bandwidth crossing your interface. Another thing to try is get a copy of LANforge and emulate the traffic with as many vlans as you'd like.
Nov
18
comment what is the fastest and most reliable way of transferring a lot of files?
@bahamat thank you for making me look at the question again. My suggestion only seems appropriate if the transfer can occur over a VPN then. For an Internet transfer, I would certainly use ssh as well.
Nov
17
awarded  Commentator
Nov
17
comment what is the fastest and most reliable way of transferring a lot of files?
You can use faster encryption mechanisms if you need to. But you don't necessarily need to pipe this thru ssh. I prefer to set the -O and -I ports on mbuffer on both sides. Even tho this is now two commands, you skip the encryption and maximize network bandwidth by buffering both ends. I'm sending a tar stream at 720+Mbps on my local LAN with the equivalent of tar -cf - .|mbuffer -m128k -s 256M -I 9090 & mbuffer -m128k -s 256M -O host:9090 | tar -xf -
Nov
17
comment what is the fastest and most reliable way of transferring a lot of files?
well, given the affordability of gigabit LAN hardware, if its a LAN transfer, the time spent writing via eSATA to a single spindle is not all that attractive.
Nov
7
comment ZFS file deletion and its relationship to disk space
Be very careful when using the dedup option. Distributions like FreeNAS typically have FAQs on why ZFS is terribly slow when running dedup: it takes about 5MB of memory 1GB of space to dedup, so if you have 5TB of space, you might need 25GB ram to use it efficiently. See this writeup: constantin.glez.de/blog/2011/07/zfs-dedupe-or-not-dedupe
May
18
comment Linux e1000e (Intel networking driver) problems galore, where do I start?
Bummer - won't work for me: ethtool -e p11p5 | grep 0x0010 | awk '{print "0x"$13$12$15$14}' 0x105e8086
May
18
comment Linux e1000e (Intel networking driver) problems galore, where do I start?
ubuntu 13.04 with 3.9.2 - this does not work for me
May
14
awarded  Caucus
Aug
20
answered Apache: Redirect 404 and ErrorDocument 404 difference
Feb
7
awarded  Revival
Jan
31
awarded  Yearling
Jul
15
awarded  Nice Answer
Feb
2
answered Performance issues concurrently running MySQL and SQL Sever
Feb
2
answered MySQL not working under apache/php
Feb
2
answered MySQL 4.1 crashes with “Database was not shut down normally!”