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Further improvements to Delta2 performance.

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Fix the byteswap macros.
Start adding assertions.
This commit is contained in:
Moinak Ghosh 2012-12-28 22:12:38 +05:30
parent 26a4f42506
commit 36d95276ee
3 changed files with 60 additions and 49 deletions
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82
delta2/delta2.c
View file

@ -43,7 +43,11 @@
* 64-bit encoded value is of the following format * 64-bit encoded value is of the following format
* Most Significant Byte = Stride length * Most Significant Byte = Stride length
* Remaining Bytes = Number of bytes in the span * Remaining Bytes = Number of bytes in the span
*
* We optimize for little-endian, so values are stored and interpreted
* in little-endian order.
*/ */
#include <stdio.h> #include <stdio.h>
#include <string.h> #include <string.h>
#include <utils.h> #include <utils.h>
@ -82,16 +86,12 @@
#define DELTA2_CHUNK (4096) #define DELTA2_CHUNK (4096)
/* /*
* Byteswap macros. We optimize for little-endian, so values are stored * Stride values to be checked. As of this implementation strides only
* and interpreted in little-endian order. * upto 8 bytes (uint64_t) are supported.
*/ */
#if BYTE_ORDER == BIG_ENDIAN #define NSTRIDES 4
#define HTONLL htonll static uchar_t strides[NSTRIDES] = {3, 5, 7, 8};
#define NTOHLL ntohll
#else
#define HTONLL
#define NTOHLL
#endif
static int delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen, static int delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen,
int rle_thresh, int last_encode, int *hdr_ovr); int rle_thresh, int last_encode, int *hdr_ovr);
@ -104,6 +104,9 @@ delta2_encode(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen, int
return (-1); return (-1);
} }
if (rle_thresh < MIN_THRESH)
return (-1);
if (*dstlen < DELTA2_CHUNK) { if (*dstlen < DELTA2_CHUNK) {
int hdr_ovr; int hdr_ovr;
int rv; int rv;
@ -123,7 +126,7 @@ delta2_encode(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen, int
dstend = dst + *dstlen; dstend = dst + *dstlen;
slen = srclen; slen = srclen;
pending = 0; pending = 0;
*((uint64_t *)dstpos) = HTONLL(srclen); *((uint64_t *)dstpos) = LE64(srclen);
dstpos += MAIN_HDR; dstpos += MAIN_HDR;
lastdst = dstpos; lastdst = dstpos;
lastsrc = srcpos; lastsrc = srcpos;
@ -154,7 +157,7 @@ delta2_encode(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen, int
} else { } else {
if (pending) { if (pending) {
pending &= MSB_SETZERO_MASK; pending &= MSB_SETZERO_MASK;
*((uint64_t *)lastdst) = HTONLL(pending); *((uint64_t *)lastdst) = LE64(pending);
lastdst += sizeof (uint64_t); lastdst += sizeof (uint64_t);
memcpy(lastdst, lastsrc, pending); memcpy(lastdst, lastsrc, pending);
pending = 0; pending = 0;
@ -170,7 +173,7 @@ delta2_encode(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen, int
} }
if (pending) { if (pending) {
pending &= MSB_SETZERO_MASK; pending &= MSB_SETZERO_MASK;
*((uint64_t *)lastdst) = HTONLL(pending); *((uint64_t *)lastdst) = LE64(pending);
lastdst += sizeof (uint64_t); lastdst += sizeof (uint64_t);
if (lastdst + pending > dstend) { if (lastdst + pending > dstend) {
DEBUG_STAT_EN(fprintf(stderr, "No Delta\n")); DEBUG_STAT_EN(fprintf(stderr, "No Delta\n"));
@ -195,21 +198,17 @@ delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen
uint64_t cnt, val, sval; uint64_t cnt, val, sval;
uint64_t vl1, vl2, vld1, vld2; uint64_t vl1, vl2, vld1, vld2;
uchar_t *pos, *pos2, stride, st1; uchar_t *pos, *pos2, stride, st1;
uchar_t strides[4] = {3, 5, 7, 8}; int st;
int st, sz;
if (rle_thresh < MIN_THRESH) assert(srclen == *dstlen);
return (-1);
gtot1 = ULL_MAX; gtot1 = ULL_MAX;
stride = 0; stride = 0;
val = 0;
tot = 0; tot = 0;
sz = sizeof (strides) / sizeof (strides[0]);
/* /*
* Estimate which stride length gives the max reduction given rle_thresh. * Estimate which stride length gives the max reduction given rle_thresh.
*/ */
for (st = 0; st < sz; st++) { for (st = 0; st < NSTRIDES; st++) {
int gt; int gt;
snum = 0; snum = 0;
@ -223,9 +222,10 @@ delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen
sval = ((sval << 3) - 1); sval = ((sval << 3) - 1);
sval = (1ULL << sval); sval = (1ULL << sval);
sval |= (sval - 1); sval |= (sval - 1);
val = 0;
for (cnt = 0; cnt < (srclen - sizeof (cnt)); cnt += st1) { for (cnt = 0; cnt < (srclen - sizeof (cnt)); cnt += st1) {
vl2 = *((uint64_t *)pos); vl2 = *((uint64_t *)pos);
vl2 = HTONLL(vl2); vl2 = LE64(vl2);
vl2 &= sval; vl2 &= sval;
vld2 = vl2 - vl1; vld2 = vl2 - vl1;
if (vld1 != vld2) { if (vld1 != vld2) {
@ -268,8 +268,12 @@ delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen
} }
} }
if ( !(gtot1 < srclen && srclen - gtot1 > (DELTA_HDR + LIT_HDR + MAIN_HDR) && gtot1 < *dstlen) ) { /*
if (srclen >= DELTA2_CHUNK) { * No need to check for destination buffer overflow since
* dstlen == srclen always.
*/
if ( gtot1 > (srclen - (DELTA_HDR + LIT_HDR + MAIN_HDR)) ) {
if (srclen == DELTA2_CHUNK) {
if (tot > 0) if (tot > 0)
*dstlen = tot; *dstlen = tot;
} }
@ -287,7 +291,7 @@ delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen
pos2 = dst; pos2 = dst;
vl2 = *((uint64_t *)pos); vl2 = *((uint64_t *)pos);
vl2 = HTONLL(vl2); vl2 = LE64(vl2);
val = stride; val = stride;
val = ((val << 3) - 1); val = ((val << 3) - 1);
val = (1ULL << val); val = (1ULL << val);
@ -297,14 +301,14 @@ delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen
for (cnt = 0; cnt < (srclen - sizeof (cnt)); cnt += stride) { for (cnt = 0; cnt < (srclen - sizeof (cnt)); cnt += stride) {
vl2 = *((uint64_t *)pos); vl2 = *((uint64_t *)pos);
vl2 = HTONLL(vl2); vl2 = LE64(vl2);
vl2 &= val; vl2 &= val;
vld2 = vl2 - vl1; vld2 = vl2 - vl1;
if (vld1 != vld2) { if (vld1 != vld2) {
if (snum > rle_thresh) { if (snum > rle_thresh) {
if (gtot1 > 0) { if (gtot1 > 0) {
gtot1 &= MSB_SETZERO_MASK; gtot1 &= MSB_SETZERO_MASK;
*((uint64_t *)pos2) = HTONLL(gtot1); *((uint64_t *)pos2) = LE64(gtot1);
pos2 += sizeof (uint64_t); pos2 += sizeof (uint64_t);
DEBUG_STAT_EN(*hdr_ovr += LIT_HDR); DEBUG_STAT_EN(*hdr_ovr += LIT_HDR);
memcpy(pos2, pos - (gtot1+snum), gtot1); memcpy(pos2, pos - (gtot1+snum), gtot1);
@ -318,11 +322,11 @@ delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen
gtot2 = stride; gtot2 = stride;
gtot2 <<= MSB_SHIFT; gtot2 <<= MSB_SHIFT;
gtot2 |= (snum & MSB_SETZERO_MASK); gtot2 |= (snum & MSB_SETZERO_MASK);
*((uint64_t *)pos2) = HTONLL(gtot2); *((uint64_t *)pos2) = LE64(gtot2);
pos2 += sizeof (uint64_t); pos2 += sizeof (uint64_t);
*((uint64_t *)pos2) = HTONLL(sval); *((uint64_t *)pos2) = LE64(sval);
pos2 += sizeof (uint64_t); pos2 += sizeof (uint64_t);
*((uint64_t *)pos2) = HTONLL(vld1); *((uint64_t *)pos2) = LE64(vld1);
pos2 += sizeof (uint64_t); pos2 += sizeof (uint64_t);
DEBUG_STAT_EN(*hdr_ovr += DELTA_HDR); DEBUG_STAT_EN(*hdr_ovr += DELTA_HDR);
} else { } else {
@ -341,7 +345,7 @@ delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen
if (snum > rle_thresh) { if (snum > rle_thresh) {
if (gtot1 > 0) { if (gtot1 > 0) {
gtot1 &= MSB_SETZERO_MASK; gtot1 &= MSB_SETZERO_MASK;
*((uint64_t *)pos2) = HTONLL(gtot1); *((uint64_t *)pos2) = LE64(gtot1);
pos2 += sizeof (uint64_t); pos2 += sizeof (uint64_t);
DEBUG_STAT_EN(*hdr_ovr += LIT_HDR); DEBUG_STAT_EN(*hdr_ovr += LIT_HDR);
memcpy(pos2, pos - (gtot1+snum), gtot1); memcpy(pos2, pos - (gtot1+snum), gtot1);
@ -351,18 +355,18 @@ delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen
gtot2 = stride; gtot2 = stride;
gtot2 <<= MSB_SHIFT; gtot2 <<= MSB_SHIFT;
gtot2 |= (snum & MSB_SETZERO_MASK); gtot2 |= (snum & MSB_SETZERO_MASK);
*((uint64_t *)pos2) = HTONLL(gtot2); *((uint64_t *)pos2) = LE64(gtot2);
pos2 += sizeof (uint64_t); pos2 += sizeof (uint64_t);
*((uint64_t *)pos2) = HTONLL(sval); *((uint64_t *)pos2) = LE64(sval);
pos2 += sizeof (uint64_t); pos2 += sizeof (uint64_t);
*((uint64_t *)pos2) = HTONLL(vld1); *((uint64_t *)pos2) = LE64(vld1);
pos2 += sizeof (uint64_t); pos2 += sizeof (uint64_t);
DEBUG_STAT_EN(*hdr_ovr += DELTA_HDR); DEBUG_STAT_EN(*hdr_ovr += DELTA_HDR);
} else if (last_encode) { } else if (last_encode) {
gtot1 += snum; gtot1 += snum;
gtot1 &= MSB_SETZERO_MASK; gtot1 &= MSB_SETZERO_MASK;
*((uint64_t *)pos2) = HTONLL(gtot1); *((uint64_t *)pos2) = LE64(gtot1);
pos2 += sizeof (uint64_t); pos2 += sizeof (uint64_t);
DEBUG_STAT_EN(*hdr_ovr += LIT_HDR); DEBUG_STAT_EN(*hdr_ovr += LIT_HDR);
memcpy(pos2, pos - gtot1, gtot1); memcpy(pos2, pos - gtot1, gtot1);
@ -380,7 +384,7 @@ delta2_encode_real(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen
* literal run. * literal run.
*/ */
val &= MSB_SETZERO_MASK; val &= MSB_SETZERO_MASK;
*((uint64_t *)pos2) = HTONLL(val); *((uint64_t *)pos2) = LE64(val);
pos2 += sizeof (uint64_t); pos2 += sizeof (uint64_t);
for (cnt = 0; cnt < val; cnt++) { for (cnt = 0; cnt < val; cnt++) {
*pos2 = *pos; *pos2 = *pos;
@ -409,7 +413,7 @@ delta2_decode(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen)
DEBUG_STAT_EN(strt = get_wtime_millis()); DEBUG_STAT_EN(strt = get_wtime_millis());
last = pos + srclen; last = pos + srclen;
olen = NTOHLL(*((uint64_t *)pos)); olen = LE64(*((uint64_t *)pos));
if (*dstlen < olen) { if (*dstlen < olen) {
fprintf(stderr, "DELTA2 Decode: Destination buffer too small.\n"); fprintf(stderr, "DELTA2 Decode: Destination buffer too small.\n");
return (-1); return (-1);
@ -420,7 +424,7 @@ delta2_decode(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen)
while (pos < last) { while (pos < last) {
val = *((uint64_t *)pos); val = *((uint64_t *)pos);
val = NTOHLL(val); val = LE64(val);
flags = (val >> MSB_SHIFT) & 0xff; flags = (val >> MSB_SHIFT) & 0xff;
if (flags == 0) { if (flags == 0) {
@ -442,9 +446,9 @@ delta2_decode(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen)
stride = flags; stride = flags;
rcnt = val & MSB_SETZERO_MASK; rcnt = val & MSB_SETZERO_MASK;
pos += sizeof (rcnt); pos += sizeof (rcnt);
sval = NTOHLL(*((uint64_t *)pos)); sval = LE64(*((uint64_t *)pos));
pos += sizeof (sval); pos += sizeof (sval);
delta = NTOHLL(*((uint64_t *)pos)); delta = LE64(*((uint64_t *)pos));
pos += sizeof (delta); pos += sizeof (delta);
if (out + rcnt > *dstlen) { if (out + rcnt > *dstlen) {
fprintf(stderr, "DELTA2 Decode: Destination buffer overflow. Corrupt data.\n"); fprintf(stderr, "DELTA2 Decode: Destination buffer overflow. Corrupt data.\n");
@ -462,7 +466,7 @@ delta2_decode(uchar_t *src, uint64_t srclen, uchar_t *dst, uint64_t *dstlen)
*/ */
for (cnt = 0; cnt < rcnt/stride; cnt++) { for (cnt = 0; cnt < rcnt/stride; cnt++) {
val = (sval & vl); val = (sval & vl);
*((uint64_t *)pos1) = NTOHLL(val); *((uint64_t *)pos1) = LE64(val);
out += stride; out += stride;
sval += delta; sval += delta;
pos1 += stride; pos1 += stride;

8
utils/heapq.c
View file

@ -70,8 +70,8 @@ _siftupmax(heap_t *h, __TYPE spos, __TYPE epos)
endpos = h->len; endpos = h->len;
heap = h->ary; heap = h->ary;
#ifdef ERROR_CHK #ifdef ERROR_CHK
if (pos >= endpos) { if (spos >= endpos) {
fprintf(stderr, "_siftupmax: index out of range: %u, len: %u\n", pos, endpos); fprintf(stderr, "_siftupmax: index out of range: %u, len: %u\n", spos, endpos);
return -1; return -1;
} }
#endif #endif
@ -117,8 +117,8 @@ _siftupmax_s(heap_t *h, __TYPE spos)
endpos = h->len; endpos = h->len;
heap = h->ary; heap = h->ary;
#ifdef ERROR_CHK #ifdef ERROR_CHK
if (pos >= endpos) { if (spos >= endpos) {
fprintf(stderr, "_siftupmax: index out of range: %u, len: %u\n", pos, endpos); fprintf(stderr, "_siftupmax: index out of range: %u, len: %u\n", spos, endpos);
return -1; return -1;
} }
#endif #endif

7
utils/utils.h
View file

@ -34,6 +34,7 @@
#include <inttypes.h> #include <inttypes.h>
#include <stdint.h> #include <stdint.h>
#include <assert.h>
#ifdef __cplusplus #ifdef __cplusplus
extern "C" { extern "C" {
@ -67,6 +68,11 @@ typedef int64_t bsize_t;
# ifndef ntonll # ifndef ntonll
# define ntohll(x) (x) # define ntohll(x) (x)
# endif # endif
# if !defined(sun) && !defined (__sun)
# define LE64(x) __bswap_64(x)
# else
# define LE64(x) BSWAP_64(x)
# endif
#else #else
# if !defined(sun) && !defined (__sun) # if !defined(sun) && !defined (__sun)
# ifndef htonll # ifndef htonll
@ -76,6 +82,7 @@ typedef int64_t bsize_t;
# define ntohll(x) __bswap_64(x) # define ntohll(x) __bswap_64(x)
# endif # endif
# endif # endif
# define LE64(x) (x)
#endif #endif