Hi Jaegeuk, Happy Chinese New Year! :)
On 2017/1/24 12:35, Jaegeuk Kim wrote: > Hi Chao, > > On 01/22, Chao Yu wrote: >> In scenario of intensively node allocation, free nids will be ran out >> soon, then it needs to stop to load free nids by traversing NAT blocks, >> in worse case, if NAT blocks does not be cached in memory, it generates >> IOs which slows down our foreground operations. >> >> In order to speed up node allocation, in this patch we introduce a new >> option named "nid cache", when turns on this option, it will load all >> nat entries in NAT blocks when doing mount, and organize all free nids >> in a bitmap, for any operations related to free nid, we will query and >> set the new prebuilded bitmap instead of reading and lookuping NAT >> blocks, so performance of node allocation can be improved. >> > > How does this affect mount time and memory consumption? Sorry for the delay. Let me figure out some numbers later. > IMO, if those do not > raise huge concerns, we would be able to consider just replacing current free > nid list with this bitmap. Yup, I agree with you. Thanks,
