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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Test your total disk IO capacity, regardless of caching, to find out how fast the TRUE speed of your disks are

Terminal - Test your total disk IO capacity, regardless of caching, to find out how fast the TRUE speed of your disks are
time dd if=/dev/zero of=blah.out oflag=direct bs=256M count=1
2009-07-15 07:17:32
User: olorin
Functions: dd time
Test your total disk IO capacity, regardless of caching, to find out how fast the TRUE speed of your disks are

Let dd use direct I/O to write directly to the disk without any caching. You'll encounter very different results with different block sizes (try with 1k, 4k, 1M, ... and appropriate count values).


There is 1 alternative - vote for the best!

Terminal - Alternatives
time (dd if=/dev/zero of=blah.out bs=256M count=1 ; sync )
2009-07-14 20:19:23
User: tkunz
Functions: dd sync time

Depending on the speed of you system, amount of RAM, and amount of free disk space, you can find out practically how fast your disks really are. When it completes, take the number of MB copied, and divide by the line showing the "real" number of seconds. In the sample output, the cached value shows a write speed of 178MB/s, which is unrealistic, while the calculated value using the output and the number of seconds shows it to be more like 35MB/s, which is feasible.

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