强制backfill替代recover避免阻塞

前言

做recover会触发阻塞，引起前端的IO卡住，可以通过参数避免这个情况

调整参数

# the number of entries to keep in the pg log when trimming it. Defaults to 3000.
osd_min_pg_log_entries = 1

# the max entries, say when degraded, before we trim. Defaults to 10000.
osd_max_pg_log_entries = 2

是否需要做backfill是通过pg log判断的，可以通过调整上面的参数来强制做backfill