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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

create an emergency swapfile when the existing swap space is getting tight

Terminal - create an emergency swapfile when the existing swap space is getting tight
sudo dd if=/dev/zero of=/swapfile bs=1024 count=1024000;sudo mkswap /swapfile; sudo swapon /swapfile
2009-05-27 21:10:50
User: dcabanis
Functions: dd mkswap sudo swapon
create an emergency swapfile when the existing swap space is getting tight

Create a temporary file that acts as swap space. In this example it's a 1GB file at the root of the file system. This additional capacity is added to the existing swap space.


There is 1 alternative - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

sudo bximage -hd -mode=flat -size=1024 -q /swapfile; sudo mkswap /swapfile; sudo swapon /swapfile

As it is much less resource (i.e. cpu and hd) consuming

time dd if=/dev/zero of=/swapfile bs=1024 count=1024000


dd if=/dev/zero of=/swapfile bs=1024 count=1024000 0.33s user 7.34s system 34% cpu 22.552 total

time bximage -hd -mode=flat -size=1024 -q .swapfile


bximage -hd -mode=flat -size=1024 -q /swapfile 0.00s user 0.00s system 58% cpu 0.005 total

time /sbin/mkswap /swapfile

mkswap: d.img: warning: don't erase bootbits sectors

on whole disk. Use -f to force.

Setting up swapspace version 1, size = 1048316 KiB

no label, UUID=xxxxxxxx

/sbin/mkswap /swapfile 0.00s user 0.00s system 0% cpu 0.647 total

bximage is part of boche emulator - but is is suitable as we are not interested in any particular content (zero) so we don't mind garbage inside.

Comment by MaciejPiechotka 417 weeks and 1 day ago

Your point of view

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