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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 are 4 alternatives - vote for the best!

Terminal - Alternatives

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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 304 weeks and 5 days ago

Your point of view

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