Hi Coly Thanks so much for your response. On 2019/5/30 17:03, Coly Li wrote: > On 2019/5/30 11:22 上午, Jianchao Wang wrote: >> Dear guys >> >> We have an about 200T disk array and want to use a 2T ssd to cache it. >> How many memory and ssd space are consumed by the bcache when the caching device >> is nearly used up ? > > Hi Jianchao, > > It heavily depends on your workload for the SSD and memory consuming. It > is better to test with your workload and get a number. > > For a full random I/O on the 200T disk array, bcache may occupy around > 75% free space of the SSD, and as many as memory it can require from system. > I mean the only the metadata of bcache, namely the map btree, log, etc. Thanks Jianchao
