After the sysbench prepare operation is completed, about 48883MB of db data is generated. I set the fast partition to 30GB, so in the sysbench run stage, eviction was taking place. Mark Nelson <mnelson@redhat.com> 于2019年10月12日周六 上午12:15写道：
Hi Honggang,
I personally I find this very exciting! I was hoping that we might eventually try local caching in bluestore especially given trends for larger NVMe devices and pmem. When you were running performance tests, did you run any tests where the data set size was significantly larger than the available "fast" local tier cache (ie so that eviction was taking place)? In the past, that's been the area we've really needed to focus on getting right.
Mark
On 10/11/19 11:04 AM, Honggang(Joseph) Yang wrote:
Hi,
We implemented a new cache tier mode - local mode. In this mode, an osd is configured to manage two data devices, one is fast device, one is slow device. Hot objects are promoted from slow device to fast device, and demoted from fast device to slow device when they become cold.
The introduction of tier local mode in detail is https://tracker.ceph.com/issues/42286
tier local mode: https://github.com/yanghonggang/ceph/commits/wip-tier-new
This work is based on ceph v12.2.5. I'm glad to port it to master branch if needed.
Any advice and suggestions will be greatly appreciated.
thx,
Yang Honggang