LU-14762 lmv: compare space to mkdir on parent MDT

[fs/lustre-release.git] / lustre / obdclass / lu_tgt_descs.c

diff --git a/lustre/obdclass/lu_tgt_descs.c b/lustre/obdclass/lu_tgt_descs.c
index 04e2330..d872db4 100644 (file)
--- a/lustre/obdclass/lu_tgt_descs.c
+++ b/lustre/obdclass/lu_tgt_descs.c
@@ -228,14 +228,15 @@ static inline __u64 tgt_statfs_iavail(struct lu_tgt_desc *tgt)
 void lu_tgt_qos_weight_calc(struct lu_tgt_desc *tgt)
 {
        struct lu_tgt_qos *ltq = &tgt->ltd_qos;
-       __u64 temp, temp2;
+       __u64 penalty;
 
-       temp = (tgt_statfs_bavail(tgt) >> 16) * (tgt_statfs_iavail(tgt) >> 8);
-       temp2 = ltq->ltq_penalty + ltq->ltq_svr->lsq_penalty;
-       if (temp < temp2)
+       ltq->ltq_avail = (tgt_statfs_bavail(tgt) >> 16) *
+                        (tgt_statfs_iavail(tgt) >> 8);
+       penalty = ltq->ltq_penalty + ltq->ltq_svr->lsq_penalty;
+       if (ltq->ltq_avail < penalty)
                ltq->ltq_weight = 0;
        else
-               ltq->ltq_weight = temp - temp2;
+               ltq->ltq_weight = ltq->ltq_avail - penalty;
 }
 EXPORT_SYMBOL(lu_tgt_qos_weight_calc);
 
@@ -273,13 +274,21 @@ int lu_tgt_descs_init(struct lu_tgt_descs *ltd, bool is_mdt)
        init_rwsem(&ltd->ltd_qos.lq_rw_sem);
        set_bit(LQ_DIRTY, &ltd->ltd_qos.lq_flags);
        set_bit(LQ_RESET, &ltd->ltd_qos.lq_flags);
-       /* Default priority is toward free space balance */
-       ltd->ltd_qos.lq_prio_free = 232;
-       /* Default threshold for rr (roughly 17%) */
-       ltd->ltd_qos.lq_threshold_rr = 43;
        ltd->ltd_is_mdt = is_mdt;
-       if (is_mdt)
+       /* MDT imbalance threshold is low to balance across MDTs
+        * relatively quickly, because each directory may result
+        * in a large number of files/subdirs created therein.
+        */
+       if (is_mdt) {
                ltd->ltd_lmv_desc.ld_pattern = LMV_HASH_TYPE_DEFAULT;
+               ltd->ltd_qos.lq_prio_free = LMV_QOS_DEF_PRIO_FREE * 256 / 100;
+               ltd->ltd_qos.lq_threshold_rr =
+                       LMV_QOS_DEF_THRESHOLD_RR_PCT * 256 / 100;
+       } else {
+               ltd->ltd_qos.lq_prio_free = LOV_QOS_DEF_PRIO_FREE * 256 / 100;
+               ltd->ltd_qos.lq_threshold_rr =
+                       LOV_QOS_DEF_THRESHOLD_RR_PCT * 256 / 100;
+       }
 
        return 0;
 }