it is the O_PONIES issue again!

Posted May 7, 2019 21:23 UTC (Tue) by walex (guest, #69836)
In reply to: it is the O_PONIES issue again! by naptastic
Parent article: Issues around discard

«"How the hell did you write SEVEN HUNDRED TERABYTES to this drive in two years‽"

It was the Ceph journal drive.»

And that is also because the 950 EVO does not have a persistent (supercapacitor backed) cache, and thus all 700 TB will have hit the flash chips, even if a lot of it probably was just ephemeral. Anyhow using the 950 EVO as a Ceph journal device, especially with that high rate of journaling (38GB/hour), probably cost a lot in latency to Ceph.