rename admin command count to census, report min/max on key & value s…

…izes in addition to counts & total sizes

src/protocol/admin/format.h

@@ -8,8 +8,14 @@
 #define METRIC_DESCRIBE_LEN 120 /* 34 (name) + 16 (type) + 68 (description) + CRLF */
 #define METRIC_END "END\r\n"
 #define METRIC_END_LEN (sizeof(METRIC_END) - 1)
-#define KEYCOUNT_FMT "%zu %zu %zu\r\n"
-#define KEYCOUNT_LEN 64 /* 20 * 3 (numbers) + 2 (spaces) + CRLF */
+#define CENSUS_COUNT_FMT "item count: %zu %zu %zu\r\n"
+#define CENSUS_COUNT_LEN 34 /* 12 (name string) + 20 + CRLF */
+#define CENSUS_KEY_FMT "key min: %zu, max: %zu, total: %zu\r\n"
+#define CENSUS_KEY_LEN 87 /* 9 + 7 + 9 (name strings) + 20 * 3 + CRLF */
+#define CENSUS_VAL_FMT "val min: %zu, max: %zu, total: %zu\r\n"
+#define CENSUS_VAL_LEN 87 /* 9 + 7 + 9 (name strings) + 20 * 3 + CRLF */
+#define CENSUS_FMT CENSUS_COUNT_FMT CENSUS_KEY_FMT CENSUS_VAL_FMT
+#define CENSUS_LEN CENSUS_COUNT_LEN + CENSUS_KEY_LEN + CENSUS_VAL_LEN
 
 #define VERSION_PRINTED "VERSION " VERSION_STRING "\r\n"
 

src/protocol/admin/parse.c

@@ -47,8 +47,8 @@ _get_req_type(struct request *req, struct bstring *type)
  break;
  }
 
- if (str5cmp(type->data, 'c', 'o', 'u', 'n', 't')) {
- req->type = REQ_COUNT;
+ if (str6cmp(type->data, 'c', 'e', 'n', 's', 'u', 's')) {
+ req->type = REQ_CENSUS;
  break;
  }
 

src/protocol/admin/request.h

@@ -25,7 +25,7 @@
  ACTION( REQ_UNKNOWN, "" )\
  ACTION( REQ_STATS, "stats" )\
  ACTION( REQ_VERSION, "version" )\
- ACTION( REQ_COUNT,  "count"  )\
+ ACTION( REQ_CENSUS, "census" )\
  ACTION( REQ_DUMP, "dump" )\
  ACTION( REQ_QUIT, "quit" )
 

src/server/twemcache/admin/process.c

@@ -30,6 +30,7 @@ admin_process_setup(void)
  }
 
  nmetric_perslab = METRIC_CARDINALITY(perslab[0]);
+ /* so far the largest response comes from per-slab metrics */
  /* perslab metric size <(32 + 20)B, prefix/suffix 12B, total < 64 */
  cap = MAX(nmetric, nmetric_perslab * SLABCLASS_MAX_ID) * METRIC_PRINT_LEN +
  METRIC_END_LEN;
@@ -115,22 +116,23 @@ _key_dump(struct response *rsp, struct request *req)
 }
 
 static void
-_key_count(struct response *rsp, struct request *req)
+_key_census(struct response *rsp, struct request *req)
 {
- size_t nkey, ksize, vsize;
+ size_t nkey, ktotal, vtotal, kmin, kmax, vmin, vmax;
  int ret = 0;
 
  if (req->arg.len > 0) { /* skip initial space */
  req->arg.len--;
  req->arg.data++;
  }
- log_info("count keys with prefix %.*s", req->arg.len, req->arg.data);
+ log_info("census on keys with prefix %.*s", req->arg.len, req->arg.data);
 
- item_count(&nkey, &ksize, &vsize, &req->arg);
+ item_census(&nkey, &ktotal, &kmin, &kmax, &vtotal, &vmin, &vmax, &req->arg);
  rsp->type = RSP_GENERIC;
- ret = cc_scnprintf(buf, cap, KEYCOUNT_FMT, nkey, ksize, vsize);
+ ret = cc_scnprintf(buf, cap, CENSUS_FMT, nkey, ktotal, kmin, kmax, vtotal,
+ vmin, vmax);
  if (ret < 0) {
- rsp->data = str2bstr("ERROR: cannot format key count");
+ rsp->data = str2bstr("ERROR: cannot format key census result");
  } else {
  rsp->data.len = ret;
  rsp->data.data = buf;
@@ -155,8 +157,8 @@ admin_process_request(struct response *rsp, struct request *req)
  _key_dump(rsp, req);
  break;
 
- case REQ_COUNT:
- _key_count(rsp, req);
+ case REQ_CENSUS:
+ _key_census(rsp, req);
  break;
 
  default:

src/storage/slab/item.c

@@ -384,25 +384,37 @@ item_flush(void)
 
 /* this dumps all keys (matching a prefix if given) regardless of expiry status */
 void
-item_count(size_t *nkey, size_t *ksize, size_t *vsize, struct bstring *prefix)
+item_census(size_t *nkey, size_t *ktotal, size_t *kmin, size_t *kmax,
+ size_t *vtotal, size_t *vmin, size_t *vmax, struct bstring *prefix)
 {
  uint32_t nbucket = HASHSIZE(hash_table->hash_power);
+ size_t klen, vlen;
 
  log_info("start scanning all %"PRIu32" keys", hash_table->nhash_item);
 
  *nkey = 0;
- *ksize = 0;
- *vsize = 0;
+ *ktotal = 0;
+ *vtotal = 0;
+ *kmin = SIZE_MAX;
+ *kmax = 0;
+ *vmin = SIZE_MAX;
+ *vmax = 0;
  for (uint32_t i = 0; i < nbucket; i++) {
  struct item_slh *entry = &hash_table->table[i];
  struct item *it;
 
  SLIST_FOREACH(it, entry, i_sle) {
- if (it->klen >= prefix->len &&
+ klen = it->klen;
+ vlen = it->vlen;
+ if (klen >= prefix->len &&
  cc_bcmp(prefix->data, item_key(it), prefix->len) == 0) {
  *nkey += 1;
- *ksize += it->klen;
- *vsize += it->vlen;
+ *ktotal += klen;
+ *vtotal += vlen;
+ *kmin = MIN(*kmin, klen);
+ *kmax = MAX(*kmax, klen);
+ *vmin = MIN(*vmin, vlen);
+ *vmax = MAX(*vmax, vlen);
  }
  }
 
@@ -412,6 +424,10 @@ item_count(size_t *nkey, size_t *ksize, size_t *vsize, struct bstring *prefix)
  }
  }
 
+ if (*nkey == 0) { /* report 0 on all fields if no match has been found */
+ *kmin = *vmin = 0;
+ }
+
  log_info("finish scanning all keys");
 }
 

src/storage/slab/item.h

@@ -39,10 +39,10 @@
  * | | \
  * \ | item_key()
  * item \
- * item->end, (if enabled) item_get_cas(), metadata
+ * item->end, (if used) optional metadata
  *
  * item->end is followed by:
- * - 8-byte cas, if ITEM_CAS flag is set
+ * - optional metadata
  * - key
  * - data
  */
@@ -214,6 +214,6 @@ bool item_delete(const struct bstring *key);
 void item_flush(void);
 
 /* this surveys all keys (matching a prefix if given) regardless of expiry status */
-void item_count(size_t *nkey, size_t *ksize, size_t *vsize, struct bstring *prefix);
+void item_census(size_t *nkey, size_t *ktotal, size_t *kmin, size_t *kmax, size_t *vtotal, size_t *vmin, size_t *vmax, struct bstring *prefix);
 /* this dumps all keys (matching a prefix if given) regardless of expiry status */
 bool item_dump(struct bstring *prefix);