Il 17/05/2012 22:42, Josh Durgin ha scritto: > + * Fallback to more conservative semantics if setting cache > + * options fails. Ignore errors from setting rbd_cache because the > + * only possible error is that the option does not exist, and > + * librbd defaults to no caching. If write through caching cannot > + * be set up, fall back to no caching. > + */ > + if (flags & BDRV_O_NOCACHE) { > + rados_conf_set(s->cluster, "rbd_cache", "false"); > + } else { > + rados_conf_set(s->cluster, "rbd_cache", "true"); > + if (!(flags & BDRV_O_CACHE_WB)) { > + r = rados_conf_set(s->cluster, "rbd_cache_max_dirty", "0"); > + if (r < 0) { > + rados_conf_set(s->cluster, "rbd_cache", "false"); > + } > + } > + }
Last time I looked at ceph, rbd_flush was not a full flush of the cache; it only ensured that the pending requests were sent. So my questions are: 1) has this changed? does rbd_flush now flush dirty items when rbd_cache_max_dirty > 0? 2) should the usage of a cache be conditional on LIBRBD_VERSION_CODE >= LIBRBD_VERSION(0, 1, 1)? Thanks, Paolo