No Space Left on Device

Re:No Space Left on Device by Xylakant on Tuesday September 06, 2016 @02:42AM (#12434019)

Since the root cause is a hash collision in the dir_index code you might just have been lucky and the author of the article unlucky.

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Re:No Space Left on Device by rshm on Tuesday September 06, 2016 @03:43AM (#12434256)

Probably lucky. File names are md5 of the content, i am not sure if it helped on collision on 32 bit md4.

The linked post mentions dir_index default and tune2fs -l lists the dir_index under Filesystem features only.

Not knowing this default behavior, i was considering enabling dir_index explicitly to aid chocking rsync.

EDIT: I ran the reproduction code with 200K instead of 100K just to be sure. There was no problem creating file as well as copying all the files to a different folder. The disk was formatted about 3 months ago and mounted with default options "ext4 noatime,barrier=0 0 0" . On original as well as copied folder `ls | wc -l` still gives 200000.

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Re:No Space Left on Device by caf on Tuesday September 06, 2016 @03:23AM (#12434193)

They would have had to have been exceptionally lucky - the chance of getting no collisions in a 32 bit hash among 782292 inputs is about 10^-62.

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