mirror of
https://github.com/fluencelabs/redis
synced 2025-03-19 00:50:50 +00:00
Move logic concerned with zset ranges
This also optimizes ZREVRANGEBYSCORE for pathological cases where a sorted set contains many elements with the same score. Previously, it would traverse the list from back to front in such a case.
This commit is contained in:
Pieter Noordhuis
parent
a300477368
commit
22b9bf1594
163
src/t_zset.c
163
src/t_zset.c
@ -180,6 +180,78 @@ typedef struct {
|
||||
int minex, maxex; /* are min or max exclusive? */
|
||||
} zrangespec;
|
||||
|
||||
static inline int zslValueInMinRange(double value, zrangespec *spec) {
|
||||
return spec->minex ? (value > spec->min) : (value >= spec->min);
|
||||
}
|
||||
|
||||
static inline int zslValueInMaxRange(double value, zrangespec *spec) {
|
||||
return spec->maxex ? (value < spec->max) : (value <= spec->max);
|
||||
}
|
||||
|
||||
static inline int zslValueInRange(double value, zrangespec *spec) {
|
||||
return zslValueInMinRange(value,spec) && zslValueInMaxRange(value,spec);
|
||||
}
|
||||
|
||||
/* Returns if there is a part of the zset is in range. */
|
||||
int zslIsInRange(zskiplist *zsl, zrangespec *range) {
|
||||
zskiplistNode *x;
|
||||
|
||||
x = zsl->tail;
|
||||
if (x == NULL || !zslValueInMinRange(x->score,range))
|
||||
return 0;
|
||||
x = zsl->header->level[0].forward;
|
||||
if (x == NULL || !zslValueInMaxRange(x->score,range))
|
||||
return 0;
|
||||
return 1;
|
||||
}
|
||||
|
||||
/* Find the first node that is contained in the specified range.
|
||||
* Returns NULL when no element is contained in the range. */
|
||||
zskiplistNode *zslFirstInRange(zskiplist *zsl, zrangespec range) {
|
||||
zskiplistNode *x;
|
||||
int i;
|
||||
|
||||
/* If everything is out of range, return early. */
|
||||
if (!zslIsInRange(zsl,&range)) return NULL;
|
||||
|
||||
x = zsl->header;
|
||||
for (i = zsl->level-1; i >= 0; i--) {
|
||||
/* Go forward while *OUT* of range. */
|
||||
while (x->level[i].forward &&
|
||||
!zslValueInMinRange(x->level[i].forward->score,&range))
|
||||
x = x->level[i].forward;
|
||||
}
|
||||
|
||||
/* The tail is in range, so the previous block should always return a
|
||||
* node that is non-NULL and the last one to be out of range. */
|
||||
x = x->level[0].forward;
|
||||
redisAssert(x != NULL && zslValueInRange(x->score,&range));
|
||||
return x;
|
||||
}
|
||||
|
||||
/* Find the last node that is contained in the specified range.
|
||||
* Returns NULL when no element is contained in the range. */
|
||||
zskiplistNode *zslLastInRange(zskiplist *zsl, zrangespec range) {
|
||||
zskiplistNode *x;
|
||||
int i;
|
||||
|
||||
/* If everything is out of range, return early. */
|
||||
if (!zslIsInRange(zsl,&range)) return NULL;
|
||||
|
||||
x = zsl->header;
|
||||
for (i = zsl->level-1; i >= 0; i--) {
|
||||
/* Go forward while *IN* range. */
|
||||
while (x->level[i].forward &&
|
||||
zslValueInMaxRange(x->level[i].forward->score,&range))
|
||||
x = x->level[i].forward;
|
||||
}
|
||||
|
||||
/* The header is in range, so the previous block should always return a
|
||||
* node that is non-NULL and in range. */
|
||||
redisAssert(x != NULL && zslValueInRange(x->score,&range));
|
||||
return x;
|
||||
}
|
||||
|
||||
/* Delete all the elements with score between min and max from the skiplist.
|
||||
* Min and mx are inclusive, so a score >= min || score <= max is deleted.
|
||||
* Note that this function takes the reference to the hash table view of the
|
||||
@ -243,22 +315,6 @@ unsigned long zslDeleteRangeByRank(zskiplist *zsl, unsigned int start, unsigned
|
||||
return removed;
|
||||
}
|
||||
|
||||
/* Find the first node having a score equal or greater than the specified one.
|
||||
* Returns NULL if there is no match. */
|
||||
zskiplistNode *zslFirstWithScore(zskiplist *zsl, double score) {
|
||||
zskiplistNode *x;
|
||||
int i;
|
||||
|
||||
x = zsl->header;
|
||||
for (i = zsl->level-1; i >= 0; i--) {
|
||||
while (x->level[i].forward && x->level[i].forward->score < score)
|
||||
x = x->level[i].forward;
|
||||
}
|
||||
/* We may have multiple elements with the same score, what we need
|
||||
* is to find the element with both the right score and object. */
|
||||
return x->level[0].forward;
|
||||
}
|
||||
|
||||
/* Find the rank for an element by both score and key.
|
||||
* Returns 0 when the element cannot be found, rank otherwise.
|
||||
* Note that the rank is 1-based due to the span of zsl->header to the
|
||||
@ -847,9 +903,18 @@ void genericZrangebyscoreCommand(redisClient *c, int reverse, int justcount) {
|
||||
int withscores = 0;
|
||||
unsigned long rangelen = 0;
|
||||
void *replylen = NULL;
|
||||
int minidx, maxidx;
|
||||
|
||||
/* Parse the range arguments. */
|
||||
if (zslParseRange(c->argv[2],c->argv[3],&range) != REDIS_OK) {
|
||||
if (reverse) {
|
||||
/* Range is given as [max,min] */
|
||||
maxidx = 2; minidx = 3;
|
||||
} else {
|
||||
/* Range is given as [min,max] */
|
||||
minidx = 2; maxidx = 3;
|
||||
}
|
||||
|
||||
if (zslParseRange(c->argv[minidx],c->argv[maxidx],&range) != REDIS_OK) {
|
||||
addReplyError(c,"min or max is not a double");
|
||||
return;
|
||||
}
|
||||
@ -882,33 +947,11 @@ void genericZrangebyscoreCommand(redisClient *c, int reverse, int justcount) {
|
||||
zsetobj = o->ptr;
|
||||
zsl = zsetobj->zsl;
|
||||
|
||||
/* If reversed, assume the elements are sorted from high to low score. */
|
||||
ln = zslFirstWithScore(zsl,range.min);
|
||||
/* If reversed, get the last node in range as starting point. */
|
||||
if (reverse) {
|
||||
/* If range.min is out of range, ln will be NULL and we need to use
|
||||
* the tail of the skiplist as first node of the range. */
|
||||
if (ln == NULL) ln = zsl->tail;
|
||||
|
||||
/* zslFirstWithScore returns the first element with where with
|
||||
* score >= range.min, so backtrack to make sure the element we use
|
||||
* here has score <= range.min. */
|
||||
while (ln && ln->score > range.min) ln = ln->backward;
|
||||
|
||||
/* Move to the right element according to the range spec. */
|
||||
if (range.minex) {
|
||||
/* Find last element with score < range.min */
|
||||
while (ln && ln->score == range.min) ln = ln->backward;
|
||||
} else {
|
||||
/* Find last element with score <= range.min */
|
||||
while (ln && ln->level[0].forward &&
|
||||
ln->level[0].forward->score == range.min)
|
||||
ln = ln->level[0].forward;
|
||||
}
|
||||
ln = zslLastInRange(zsl,range);
|
||||
} else {
|
||||
if (range.minex) {
|
||||
/* Find first element with score > range.min */
|
||||
while (ln && ln->score == range.min) ln = ln->level[0].forward;
|
||||
}
|
||||
ln = zslFirstInRange(zsl,range);
|
||||
}
|
||||
|
||||
/* No "first" element in the specified interval. */
|
||||
@ -917,40 +960,24 @@ void genericZrangebyscoreCommand(redisClient *c, int reverse, int justcount) {
|
||||
return;
|
||||
}
|
||||
|
||||
/* We don't know in advance how many matching elements there
|
||||
* are in the list, so we push this object that will represent
|
||||
* the multi-bulk length in the output buffer, and will "fix"
|
||||
* it later */
|
||||
/* We don't know in advance how many matching elements there are in the
|
||||
* list, so we push this object that will represent the multi-bulk length
|
||||
* in the output buffer, and will "fix" it later */
|
||||
if (!justcount)
|
||||
replylen = addDeferredMultiBulkLength(c);
|
||||
|
||||
/* If there is an offset, just traverse the number of elements without
|
||||
* checking the score because that is done in the next loop. */
|
||||
while(ln && offset--) {
|
||||
if (reverse)
|
||||
ln = ln->backward;
|
||||
else
|
||||
ln = ln->level[0].forward;
|
||||
ln = reverse ? ln->backward : ln->level[0].forward;
|
||||
}
|
||||
|
||||
while (ln && limit--) {
|
||||
/* Check if this this element is in range. */
|
||||
/* Abort when the node is no longer in range. */
|
||||
if (reverse) {
|
||||
if (range.maxex) {
|
||||
/* Element should have score > range.max */
|
||||
if (ln->score <= range.max) break;
|
||||
} else {
|
||||
/* Element should have score >= range.max */
|
||||
if (ln->score < range.max) break;
|
||||
}
|
||||
if (!zslValueInMinRange(ln->score,&range)) break;
|
||||
} else {
|
||||
if (range.maxex) {
|
||||
/* Element should have score < range.max */
|
||||
if (ln->score >= range.max) break;
|
||||
} else {
|
||||
/* Element should have score <= range.max */
|
||||
if (ln->score > range.max) break;
|
||||
}
|
||||
if (!zslValueInMaxRange(ln->score,&range)) break;
|
||||
}
|
||||
|
||||
/* Do our magic */
|
||||
@ -961,10 +988,8 @@ void genericZrangebyscoreCommand(redisClient *c, int reverse, int justcount) {
|
||||
addReplyDouble(c,ln->score);
|
||||
}
|
||||
|
||||
if (reverse)
|
||||
ln = ln->backward;
|
||||
else
|
||||
ln = ln->level[0].forward;
|
||||
/* Move to next node */
|
||||
ln = reverse ? ln->backward : ln->level[0].forward;
|
||||
}
|
||||
|
||||
if (justcount) {
|
||||
|
||||
@ -227,6 +227,22 @@ start_server {tags {"zset"}} {
|
||||
assert_equal {f e} [r zrevrangebyscore zset (6 (3]
|
||||
assert_equal {f} [r zrevrangebyscore zset (+inf (4]
|
||||
assert_equal 2 [r zcount zset (0 (3]
|
||||
|
||||
# test empty ranges
|
||||
r zrem zset a
|
||||
r zrem zset g
|
||||
|
||||
# inclusive
|
||||
assert_equal {} [r zrangebyscore zset 6 +inf]
|
||||
assert_equal {} [r zrangebyscore zset -inf -6]
|
||||
assert_equal {} [r zrevrangebyscore zset +inf 6]
|
||||
assert_equal {} [r zrevrangebyscore zset -6 -inf]
|
||||
|
||||
# exclusive
|
||||
assert_equal {} [r zrangebyscore zset (6 (+inf]
|
||||
assert_equal {} [r zrangebyscore zset (-inf (-6]
|
||||
assert_equal {} [r zrevrangebyscore zset (+inf (6]
|
||||
assert_equal {} [r zrevrangebyscore zset (-6 (-inf]
|
||||
}
|
||||
|
||||
test "ZRANGEBYSCORE with WITHSCORES" {
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user