diff options
| -rw-r--r-- | module/zfs/arc.c | 62 |
1 files changed, 40 insertions, 22 deletions
diff --git a/module/zfs/arc.c b/module/zfs/arc.c index f28748423..242d0c8c5 100644 --- a/module/zfs/arc.c +++ b/module/zfs/arc.c @@ -1890,6 +1890,7 @@ arc_evict(arc_state_t *state, uint64_t spa, int64_t bytes, boolean_t recycle, evicted_state = (state == arc_mru) ? arc_mru_ghost : arc_mfu_ghost; +top: mutex_enter(&state->arcs_mtx); mutex_enter(&evicted_state->arcs_mtx); @@ -2005,6 +2006,15 @@ arc_evict(arc_state_t *state, uint64_t spa, int64_t bytes, boolean_t recycle, mutex_exit(&evicted_state->arcs_mtx); mutex_exit(&state->arcs_mtx); + if (list == &state->arcs_list[ARC_BUFC_DATA] && + (bytes < 0 || bytes_evicted < bytes)) { + /* Prevent second pass from recycling metadata into data */ + recycle = FALSE; + type = ARC_BUFC_METADATA; + list = &state->arcs_list[type]; + goto top; + } + if (bytes_evicted < bytes) dprintf("only evicted %lld bytes from %x\n", (longlong_t)bytes_evicted, state); @@ -2146,16 +2156,9 @@ arc_adjust(void) adjustment = MIN((int64_t)(arc_size - arc_c), (int64_t)(arc_anon->arcs_size + arc_mru->arcs_size - arc_p)); - if (adjustment > 0 && arc_mru->arcs_lsize[ARC_BUFC_DATA] > 0) { - delta = MIN(arc_mru->arcs_lsize[ARC_BUFC_DATA], adjustment); + if (adjustment > 0 && arc_mru->arcs_size > 0) { + delta = MIN(arc_mru->arcs_size, adjustment); (void) arc_evict(arc_mru, 0, delta, FALSE, ARC_BUFC_DATA); - adjustment -= delta; - } - - if (adjustment > 0 && arc_mru->arcs_lsize[ARC_BUFC_METADATA] > 0) { - delta = MIN(arc_mru->arcs_lsize[ARC_BUFC_METADATA], adjustment); - (void) arc_evict(arc_mru, 0, delta, FALSE, - ARC_BUFC_METADATA); } /* @@ -2164,17 +2167,9 @@ arc_adjust(void) adjustment = arc_size - arc_c; - if (adjustment > 0 && arc_mfu->arcs_lsize[ARC_BUFC_DATA] > 0) { - delta = MIN(adjustment, arc_mfu->arcs_lsize[ARC_BUFC_DATA]); + if (adjustment > 0 && arc_mfu->arcs_size > 0) { + delta = MIN(arc_mfu->arcs_size, adjustment); (void) arc_evict(arc_mfu, 0, delta, FALSE, ARC_BUFC_DATA); - adjustment -= delta; - } - - if (adjustment > 0 && arc_mfu->arcs_lsize[ARC_BUFC_METADATA] > 0) { - int64_t delta = MIN(adjustment, - arc_mfu->arcs_lsize[ARC_BUFC_METADATA]); - (void) arc_evict(arc_mfu, 0, delta, FALSE, - ARC_BUFC_METADATA); } /* @@ -2752,6 +2747,8 @@ arc_get_data_buf(arc_buf_t *buf) arc_state_t *state = buf->b_hdr->b_state; uint64_t size = buf->b_hdr->b_size; arc_buf_contents_t type = buf->b_hdr->b_type; + arc_buf_contents_t evict = ARC_BUFC_DATA; + boolean_t recycle = TRUE; arc_adapt(size, state); @@ -2792,7 +2789,24 @@ arc_get_data_buf(arc_buf_t *buf) mfu_space > arc_mfu->arcs_size) ? arc_mru : arc_mfu; } - if ((buf->b_data = arc_evict(state, 0, size, TRUE, type)) == NULL) { + /* + * Evict data buffers prior to metadata buffers, unless we're + * over the metadata limit and adding a metadata buffer. + */ + if (type == ARC_BUFC_METADATA) { + if (arc_meta_used >= arc_meta_limit) + evict = ARC_BUFC_METADATA; + else + /* + * In this case, we're evicting data while + * adding metadata. Thus, to prevent recycling a + * data buffer into a metadata buffer, recycling + * is disabled in the following arc_evict call. + */ + recycle = FALSE; + } + + if ((buf->b_data = arc_evict(state, 0, size, recycle, evict)) == NULL) { if (type == ARC_BUFC_METADATA) { buf->b_data = zio_buf_alloc(size); arc_space_consume(size, ARC_SPACE_DATA); @@ -2803,8 +2817,10 @@ arc_get_data_buf(arc_buf_t *buf) * via the prune callback to drop references. The * prune callback in run in the context of the reclaim * thread to avoid deadlocking on the hash_lock. + * Of course, only do this when recycle is true. */ - cv_signal(&arc_reclaim_thr_cv); + if (recycle) + cv_signal(&arc_reclaim_thr_cv); } else { ASSERT(type == ARC_BUFC_DATA); buf->b_data = zio_data_buf_alloc(size); @@ -2812,7 +2828,9 @@ arc_get_data_buf(arc_buf_t *buf) atomic_add_64(&arc_size, size); } - ARCSTAT_BUMP(arcstat_recycle_miss); + /* Only bump this if we tried to recycle and failed */ + if (recycle) + ARCSTAT_BUMP(arcstat_recycle_miss); } ASSERT(buf->b_data != NULL); out: |