[supremesaboteur]

I assume the thinking goes like this :

ZFS was designed for enterprises. Enterprise software has requirements of high stability, scale etc. Google is probably on the extreme end of these problems. So if Google considered and rejected ZFS it probably means it was not very good.

What probably really happened was that Google was already too invested in Google File System and therefore did not give other file systems a fair chance

[mjevans]

Google's big enough that it, most likely, has something that the public ceph project is a pale imitation of.

Actually, they're big enough that something between what ceph can do and what backblaze does is probably their /archive/ backend.

They probably have all of the fast stuff on 'disposable' temporary copies in RAM or SSDs.

[petters]

GFS does not really solve the same problem as ZFS, I think.