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Simplify the BDZ compression function, making it smaller at the same 

time. Fixes a bug where non-minimal hash functions could be created.
Add regression tests for BDZ, including the map output functionality.
This commit is contained in:
joerg 2012-09-25 20:53:46 +00:00
parent d0eacb2c29
commit 4edfbdbb40
5 changed files with 125 additions and 165 deletions
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4
tests/usr.bin/nbperf/h_nbperf.sh
View File

@ -1,5 +1,5 @@
#!/bin/sh #!/bin/sh
# $NetBSD: h_nbperf.sh,v 1.1 2012/07/22 20:38:20 joerg Exp $ # $NetBSD: h_nbperf.sh,v 1.2 2012/09/25 20:53:46 joerg Exp $
# #
# Copyright (c) 2012 The NetBSD Foundation, Inc. # Copyright (c) 2012 The NetBSD Foundation, Inc.
# All rights reserved. # All rights reserved.
@ -27,6 +27,6 @@
# #
set -e set -e
head -n $4 $1 | nbperf -a $2 > hash.c 2> /dev/null head -n $4 $1 | nbperf -m hash.map -o hash.c -a $2 2> /dev/null
cc -o testprog -I. $5 cc -o testprog -I. $5
head -n $4 $1 | ./testprog | $3 head -n $4 $1 | ./testprog | $3

4
tests/usr.bin/nbperf/hash_driver.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: hash_driver.c,v 1.1 2012/07/22 20:38:20 joerg Exp $ */ /* $NetBSD: hash_driver.c,v 1.2 2012/09/25 20:53:46 joerg Exp $ */
/*- /*-
* Copyright (c) 2012 The NetBSD Foundation, Inc. * Copyright (c) 2012 The NetBSD Foundation, Inc.
* All rights reserved. * All rights reserved.
@ -46,7 +46,7 @@ main(void)
while ((len = getline(&line, &len, stdin)) > 0) { while ((len = getline(&line, &len, stdin)) > 0) {
if (len && line[len - 1] == '\n') if (len && line[len - 1] == '\n')
--len; --len;
printf("%" PRId32 "\n", 1 + hash(line, len)); printf("%" PRId32 "\n", hash(line, len));
} }
free(line); free(line);
return 0; return 0;

37
tests/usr.bin/nbperf/t_nbperf.sh
View File

@ -1,4 +1,4 @@
# $NetBSD: t_nbperf.sh,v 1.1 2012/07/22 20:38:20 joerg Exp $ # $NetBSD: t_nbperf.sh,v 1.2 2012/09/25 20:53:46 joerg Exp $
# #
# Copyright (c) 2012 The NetBSD Foundation, Inc. # Copyright (c) 2012 The NetBSD Foundation, Inc.
# All rights reserved. # All rights reserved.
@ -27,7 +27,7 @@
cleanup() cleanup()
{ {
rm -f reference.txt hash.c testprog rm -f reference.txt hash.c hash.map testprog
} }
atf_test_case chm atf_test_case chm
@ -38,10 +38,13 @@ chm_head()
chm_body() chm_body()
{ {
for n in 4 32 128 1024 65536; do for n in 4 32 128 1024 65536; do
seq $n > reference.txt seq 0 $(($n - 1)) > reference.txt
atf_check -o file:reference.txt \ atf_check -o file:reference.txt \
$(atf_get_srcdir)/h_nbperf /usr/share/dict/web2 chm cat \ $(atf_get_srcdir)/h_nbperf /usr/share/dict/web2 chm cat \
$n $(atf_get_srcdir)/hash_driver.c $n $(atf_get_srcdir)/hash_driver.c
atf_check -o file:hash.map \
$(atf_get_srcdir)/h_nbperf /usr/share/dict/web2 chm cat \
$n $(atf_get_srcdir)/hash_driver.c
done done
} }
chm_clean() chm_clean()
@ -57,10 +60,13 @@ chm3_head()
chm3_body() chm3_body()
{ {
for n in 4 32 128 1024 65536; do for n in 4 32 128 1024 65536; do
seq $n > reference.txt seq 0 $(($n - 1)) > reference.txt
atf_check -o file:reference.txt \ atf_check -o file:reference.txt \
$(atf_get_srcdir)/h_nbperf /usr/share/dict/web2 chm3 cat \ $(atf_get_srcdir)/h_nbperf /usr/share/dict/web2 chm3 cat \
$n $(atf_get_srcdir)/hash_driver.c $n $(atf_get_srcdir)/hash_driver.c
atf_check -o file:hash.map \
$(atf_get_srcdir)/h_nbperf /usr/share/dict/web2 chm3 cat \
$n $(atf_get_srcdir)/hash_driver.c
done done
} }
chm3_clean() chm3_clean()
@ -68,8 +74,31 @@ chm3_clean()
cleanup cleanup
} }
atf_test_case bdz
bdz_head()
{
atf_set "descr" "Checks bdz algorithm"
}
bdz_body()
{
for n in 4 32 128 1024 65536 131072; do
seq 0 $(($n - 1)) > reference.txt
atf_check -o file:reference.txt \
$(atf_get_srcdir)/h_nbperf /usr/share/dict/web2 bdz "sort -n" \
$n $(atf_get_srcdir)/hash_driver.c
atf_check -o file:hash.map \
$(atf_get_srcdir)/h_nbperf /usr/share/dict/web2 bdz cat \
$n $(atf_get_srcdir)/hash_driver.c
done
}
bdz_clean()
{
cleanup
}
atf_init_test_cases() atf_init_test_cases()
{ {
atf_add_test_case chm atf_add_test_case chm
atf_add_test_case chm3 atf_add_test_case chm3
atf_add_test_case bdz
} }

237
usr.bin/nbperf/nbperf-bdz.c
View File

@ -1,6 +1,6 @@
/* $NetBSD: nbperf-bdz.c,v 1.4 2011/10/21 23:47:11 joerg Exp $ */ /* $NetBSD: nbperf-bdz.c,v 1.5 2012/09/25 20:53:46 joerg Exp $ */
/*- /*-
* Copyright (c) 2009 The NetBSD Foundation, Inc. * Copyright (c) 2009, 2012 The NetBSD Foundation, Inc.
* All rights reserved. * All rights reserved.
* *
* This code is derived from software contributed to The NetBSD Foundation * This code is derived from software contributed to The NetBSD Foundation
@ -36,7 +36,7 @@
#endif #endif
#include <sys/cdefs.h> #include <sys/cdefs.h>
__RCSID("$NetBSD: nbperf-bdz.c,v 1.4 2011/10/21 23:47:11 joerg Exp $"); __RCSID("$NetBSD: nbperf-bdz.c,v 1.5 2012/09/25 20:53:46 joerg Exp $");
#include <err.h> #include <err.h>
#include <inttypes.h> #include <inttypes.h>
@ -72,10 +72,7 @@ struct state {
struct graph3 graph; struct graph3 graph;
uint32_t *visited; uint32_t *visited;
uint32_t *holes64k; uint32_t *holes64k;
uint16_t *holes256; uint16_t *holes64;
uint8_t *holes256_64;
uint8_t *holes256_128;
uint8_t *holes256_192;
uint8_t *g; uint8_t *g;
uint32_t *result_map; uint32_t *result_map;
}; };
@ -123,17 +120,8 @@ assign_nodes(struct state *state)
if (i % 65536 == 0) if (i % 65536 == 0)
state->holes64k[i >> 16] = holes; state->holes64k[i >> 16] = holes;
if (i % 256 == 0) if (i % 64 == 0)
state->holes256[i >> 8] = holes - state->holes64k[i >> 16]; state->holes64[i >> 6] = holes - state->holes64k[i >> 16];
if (i % 256 == 64)
state->holes256_64[i >> 8] = holes - state->holes256[i >> 8] - state->holes64k[i >> 16];
if (i % 256 == 128)
state->holes256_128[i >> 8] = holes - state->holes256[i >> 8] - state->holes64k[i >> 16];
if (i % 256 == 192)
state->holes256_192[i >> 8] = holes - state->holes256[i >> 8] - state->holes64k[i >> 16];
if (state->visited[i] > 1) { if (state->visited[i] > 1) {
j = state->visited[i] - 2; j = state->visited[i] - 2;
@ -143,28 +131,13 @@ assign_nodes(struct state *state)
if (state->g[i] == 3) if (state->g[i] == 3)
++holes; ++holes;
} }
if (i % 65536 != 0)
state->holes64k[(i >> 16) + 1] = holes;
if (i % 256 != 0)
state->holes256[(i >> 8) + 1] = holes - state->holes64k[((i >> 8) + 1) >> 8];
if (i % 256 != 64)
state->holes256_64[(i >> 8) + 1] = holes - state->holes256[(i >> 8) + 1] - state->holes64k[((i >> 8) + 1) >> 8];
if (i % 256 != 128)
state->holes256_128[(i >> 8) + 1] = holes - state->holes256[(i >> 8) + 1] - state->holes64k[((i >> 8) + 1) >> 8];
if (i % 256 != 192)
state->holes256_192[(i >> 8) + 1] = holes - state->holes256[(i >> 8) + 1] - state->holes64k[((i >> 8) + 1) >> 8];
} }
static void static void
print_hash(struct nbperf *nbperf, struct state *state) print_hash(struct nbperf *nbperf, struct state *state)
{ {
size_t i, j; uint64_t sum;
uint32_t sum; size_t i;
fprintf(nbperf->output, "#include <stdlib.h>\n"); fprintf(nbperf->output, "#include <stdlib.h>\n");
fprintf(nbperf->output, "#include <strings.h>\n\n"); fprintf(nbperf->output, "#include <strings.h>\n\n");
@ -175,19 +148,50 @@ print_hash(struct nbperf *nbperf, struct state *state)
"%s(const void * __restrict key, size_t keylen)\n", "%s(const void * __restrict key, size_t keylen)\n",
nbperf->hash_name); nbperf->hash_name);
fprintf(nbperf->output, "{\n"); fprintf(nbperf->output, "{\n");
fprintf(nbperf->output,
"\tstatic const uint32_t g[%" PRId32 "] = {\n",
(state->graph.v + 15) / 16);
for (i = 0; i < state->graph.v; i += 16) {
for (j = 0, sum = 0; j < 16; ++j)
sum |= (uint32_t)state->g[i + j] << (2 * j);
fprintf(nbperf->output, "%s0x%08" PRIx32 "ULL,%s", fprintf(nbperf->output,
(i / 16 % 4 == 0 ? "\t " : " "), "\tstatic const uint64_t g1[%" PRId32 "] = {\n",
(state->graph.v + 63) / 64);
sum = 0;
for (i = 0; i < state->graph.v; ++i) {
sum |= ((uint64_t)state->g[i] & 1) << (i & 63);
if (i % 64 == 63) {
fprintf(nbperf->output, "%s0x%016" PRIx64 "ULL,%s",
(i / 64 % 2 == 0 ? "\t " : " "),
sum, sum,
(i / 16 % 4 == 3 ? "\n" : "")); (i / 64 % 2 == 1 ? "\n" : ""));
sum = 0;
} }
fprintf(nbperf->output, "%s\t};\n", (i / 16 % 4 ? "\n" : "")); }
if (i % 64 != 0) {
fprintf(nbperf->output, "%s0x%016" PRIx64 "ULL,%s",
(i / 64 % 2 == 0 ? "\t " : " "),
sum,
(i / 64 % 2 == 1 ? "\n" : ""));
}
fprintf(nbperf->output, "%s\t};\n", (i % 2 ? "\n" : ""));
fprintf(nbperf->output,
"\tstatic const uint64_t g2[%" PRId32 "] = {\n",
(state->graph.v + 63) / 64);
sum = 0;
for (i = 0; i < state->graph.v; ++i) {
sum |= (((uint64_t)state->g[i] & 2) >> 1) << (i & 63);
if (i % 64 == 63) {
fprintf(nbperf->output, "%s0x%016" PRIx64 "ULL,%s",
(i / 64 % 2 == 0 ? "\t " : " "),
sum,
(i / 64 % 2 == 1 ? "\n" : ""));
sum = 0;
}
}
if (i % 64 != 0) {
fprintf(nbperf->output, "%s0x%016" PRIx64 "ULL,%s",
(i / 64 % 2 == 0 ? "\t " : " "),
sum,
(i / 64 % 2 == 1 ? "\n" : ""));
}
fprintf(nbperf->output, "%s\t};\n", (i % 2 ? "\n" : ""));
fprintf(nbperf->output, fprintf(nbperf->output,
"\tstatic const uint32_t holes64k[%" PRId32 "] = {\n", "\tstatic const uint32_t holes64k[%" PRId32 "] = {\n",
@ -200,111 +204,45 @@ print_hash(struct nbperf *nbperf, struct state *state)
fprintf(nbperf->output, "%s\t};\n", (i / 65536 % 4 ? "\n" : "")); fprintf(nbperf->output, "%s\t};\n", (i / 65536 % 4 ? "\n" : ""));
fprintf(nbperf->output, fprintf(nbperf->output,
"\tstatic const uint16_t holes256[%" PRId32 "] = {\n", "\tstatic const uint16_t holes64[%" PRId32 "] = {\n",
(state->graph.v + 255) / 256); (state->graph.v + 63) / 64);
for (i = 0; i < state->graph.v; i += 256) for (i = 0; i < state->graph.v; i += 64)
fprintf(nbperf->output, "%s0x%04" PRIx32 ",%s", fprintf(nbperf->output, "%s0x%04" PRIx32 ",%s",
(i / 256 % 4 == 0 ? "\t " : " "), (i / 64 % 4 == 0 ? "\t " : " "),
state->holes256[i >> 8], state->holes64[i >> 6],
(i / 256 % 4 == 3 ? "\n" : "")); (i / 64 % 4 == 3 ? "\n" : ""));
fprintf(nbperf->output, "%s\t};\n", (i / 256 % 4 ? "\n" : "")); fprintf(nbperf->output, "%s\t};\n", (i / 64 % 4 ? "\n" : ""));
fprintf(nbperf->output,
"\tstatic const uint8_t holes256_64[%" PRId32 "] = {\n",
(state->graph.v + 255) / 256);
for (i = 64; i < state->graph.v; i += 256)
fprintf(nbperf->output, "%s0x%02" PRIx32 ",%s",
(i / 256 % 4 == 0 ? "\t " : " "),
state->holes256_64[i >> 8],
(i / 256 % 4 == 3 ? "\n" : ""));
fprintf(nbperf->output, "%s\t};\n", (i / 256 % 4 ? "\n" : ""));
fprintf(nbperf->output,
"\tstatic const uint8_t holes256_128[%" PRId32 "] = {\n",
(state->graph.v + 255) / 256);
for (i = 128; i < state->graph.v; i += 256)
fprintf(nbperf->output, "%s0x%02" PRIx32 ",%s",
(i / 256 % 4 == 0 ? "\t " : " "),
state->holes256_128[i >> 8],
(i / 256 % 4 == 3 ? "\n" : ""));
fprintf(nbperf->output, "%s\t};\n", (i / 256 % 4 ? "\n" : ""));
fprintf(nbperf->output,
"\tstatic const uint8_t holes256_192[%" PRId32 "] = {\n",
(state->graph.v + 255) / 256);
for (i = 192; i < state->graph.v; i += 256)
fprintf(nbperf->output, "%s0x%02" PRIx32 ",%s",
(i / 256 % 4 == 0 ? "\t " : " "),
state->holes256_192[i >> 8],
(i / 256 % 4 == 3 ? "\n" : ""));
fprintf(nbperf->output, "%s\t};\n", (i / 256 % 4 ? "\n" : ""));
fprintf(nbperf->output, "\tuint64_t m;\n");
fprintf(nbperf->output, "\tuint32_t idx, i, idx2;\n");
fprintf(nbperf->output, "\tuint32_t h[%zu];\n\n", nbperf->hash_size); fprintf(nbperf->output, "\tuint32_t h[%zu];\n\n", nbperf->hash_size);
fprintf(nbperf->output, "\tuint32_t m;\n");
fprintf(nbperf->output, "\tuint32_t a1, a2, b1, b2, c1, c2, idx, idx2;\n\n");
(*nbperf->print_hash)(nbperf, "\t", "key", "keylen", "h"); (*nbperf->print_hash)(nbperf, "\t", "key", "keylen", "h");
fprintf(nbperf->output, "\n\th[0] = h[0] %% %" PRIu32 ";\n", state->graph.v); fprintf(nbperf->output, "\n\th[0] = h[0] %% %" PRIu32 ";\n",
fprintf(nbperf->output, "\th[1] = h[1] %% %" PRIu32 ";\n", state->graph.v); state->graph.v);
fprintf(nbperf->output, "\th[2] = h[2] %% %" PRIu32 ";\n", state->graph.v); fprintf(nbperf->output, "\th[1] = h[1] %% %" PRIu32 ";\n",
state->graph.v);
fprintf(nbperf->output, "\n\ta1 = h[0] >> 4;\n"); fprintf(nbperf->output, "\th[2] = h[2] %% %" PRIu32 ";\n",
fprintf(nbperf->output, "\ta2 = 2 * (h[0] & 15);\n"); state->graph.v);
fprintf(nbperf->output, "\tb1 = h[1] >> 4;\n");
fprintf(nbperf->output, "\tb2 = 2 * (h[1] & 15);\n");
fprintf(nbperf->output, "\tc1 = h[2] >> 4;\n");
fprintf(nbperf->output, "\tc2 = 2 * (h[2] & 15);\n");
fprintf(nbperf->output, fprintf(nbperf->output,
"\tidx = h[(((g[a1] >> a2) & 3) + ((g[b1] >> b2) & 3) +\n" "\tidx = 9 + ((g1[h[0] >> 6] >> (h[0] & 63)) &1)"
"\t ((g[c1] >> c2) & 3)) %% 3];\n\n"); "\t + ((g1[h[1] >> 6] >> (h[1] & 63)) & 1)"
"\t + ((g1[h[2] >> 6] >> (h[2] & 63)) & 1)"
"\t - ((g2[h[0] >> 6] >> (h[0] & 63)) & 1)"
"\t - ((g2[h[1] >> 6] >> (h[1] & 63)) & 1)"
"\t - ((g2[h[2] >> 6] >> (h[2] & 63)) & 1);"
);
fprintf(nbperf->output, fprintf(nbperf->output,
"\tswitch ((idx >> 5) & 7) {\n" "\tidx = h[idx %% 3];\n");
"\tcase 0:\n"
"\t\tidx2 = idx - holes64k[idx >> 16] - holes256[idx >> 8];\n"
"\t\tbreak;\n"
"\tcase 1: case 2:\n"
"\t\tidx2 = idx - holes64k[idx >> 16] - holes256[idx >> 8]\n"
"\t\t - holes256_64[idx >> 8];\n"
"\t\tbreak;\n"
"\tcase 3: case 4:\n"
"\t\tidx2 = idx - holes64k[idx >> 16] - holes256[idx >> 8]\n"
"\t\t - holes256_128[idx >> 8];\n"
"\t\tbreak;\n"
"\tcase 5: case 6:\n"
"\t\tidx2 = idx - holes64k[idx >> 16] - holes256[idx >> 8]\n"
"\t\t - holes256_192[idx >> 8];\n"
"\t\tbreak;\n"
"\tcase 7:\n"
"\t\tidx2 = idx - holes64k[(idx + 32) >> 16] -\n"
"\t\t holes256[(idx + 32) >> 8];\n"
"\t\tbreak;\n"
"\tdefault:\n"
"\t\tabort();\n"
"\t}\n"
"\tswitch ((idx >> 4) & 3) {\n"
"\tcase 1:\n"
"\t\tm = (g[(idx >> 4) - 1] & (g[(idx >> 4) - 1] >> 1) & 0x55555555U);\n"
"\t\tidx2 -= popcount32(m);\n"
"\tcase 0:\n"
"\t\tm = (g[idx >> 4] & (g[idx >> 4] >> 1) & 0x55555555U);\n"
"\t\tm &= ((2U << (2 * (idx & 15))) - 1);\n"
"\t\tidx2 -= popcount32(m);\n"
"\t\tbreak;\n"
"\tcase 2:\n"
"\t\tm = (g[(idx >> 4) + 1] & (g[(idx >> 4) + 1] >> 1) & 0x55555555U);\n"
"\t\tidx2 += popcount32(m);\n"
"\tcase 3:\n"
"\t\tm = (g[idx >> 4] & (g[idx >> 4] >> 1) & 0x55555555U);\n"
"\t\tm &= ~((2U << (2 * (idx & 15))) - 1);\n"
"\t\tidx2 += popcount32(m);\n"
"\t\tbreak;\n"
"\t}\n\n");
fprintf(nbperf->output, fprintf(nbperf->output,
"\treturn idx2;\n"); "\tidx2 = idx - holes64[idx >> 6] - holes64k[idx >> 16];\n"
"\tidx2 -= popcount64(g1[idx >> 6] & g2[idx >> 6]\n"
"\t & (((uint64_t)1 << idx) - 1));\n"
"\treturn idx2;");
fprintf(nbperf->output, "}\n"); fprintf(nbperf->output, "}\n");
if (nbperf->map_output != NULL) { if (nbperf->map_output != NULL) {
@ -338,19 +276,15 @@ bdz_compute(struct nbperf *nbperf)
graph3_setup(&state.graph, v, e); graph3_setup(&state.graph, v, e);
state.holes64k = calloc(sizeof(uint32_t), (v + 65535) / 65536 + 1); state.holes64k = calloc(sizeof(uint32_t), (v + 65535) / 65536);
state.holes256 = calloc(sizeof(uint16_t), (v + 255) / 256 + 1); state.holes64 = calloc(sizeof(uint16_t), (v + 63) / 64 );
state.holes256_64 = calloc(sizeof(uint8_t), (v + 255) / 256 + 1); state.g = calloc(sizeof(uint32_t), v | 63);
state.holes256_128 = calloc(sizeof(uint8_t), (v + 255) / 256 + 1);
state.holes256_192 = calloc(sizeof(uint8_t), (v + 255) / 256 + 1);
state.g = calloc(sizeof(uint32_t), v);
state.visited = calloc(sizeof(uint32_t), v); state.visited = calloc(sizeof(uint32_t), v);
state.result_map = calloc(sizeof(uint32_t), e); state.result_map = calloc(sizeof(uint32_t), e);
if (state.holes64k == NULL || state.holes256 == NULL || if (state.holes64k == NULL || state.holes64 == NULL ||
state.holes256_64 == NULL || state.holes256_128 == NULL || state.g == NULL || state.visited == NULL ||
state.holes256_192 == NULL || state.g == NULL || state.result_map == NULL)
state.visited == NULL || state.result_map == NULL)
err(1, "malloc failed"); err(1, "malloc failed");
if (graph3_hash(nbperf, &state.graph)) if (graph3_hash(nbperf, &state.graph))
@ -367,10 +301,7 @@ failed:
free(state.visited); free(state.visited);
free(state.g); free(state.g);
free(state.holes64k); free(state.holes64k);
free(state.holes256); free(state.holes64);
free(state.holes256_64);
free(state.holes256_128);
free(state.holes256_192);
free(state.result_map); free(state.result_map);
return retval; return retval;
} }

6
usr.bin/nbperf/nbperf.1
View File

@ -1,4 +1,4 @@
.\" $NetBSD: nbperf.1,v 1.4 2012/05/31 21:36:06 joerg Exp $ .\" $NetBSD: nbperf.1,v 1.5 2012/09/25 20:53:46 joerg Exp $
.\" .\"
.\" Copyright (c) 2009 The NetBSD Foundation, Inc. .\" Copyright (c) 2009 The NetBSD Foundation, Inc.
.\" All rights reserved. .\" All rights reserved.
@ -27,7 +27,7 @@
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE. .\" POSSIBILITY OF SUCH DAMAGE.
.\" .\"
.Dd May 31, 2012 .Dd September 25, 2012
.Dt NBPERF 1 .Dt NBPERF 1
.Os .Os
.Sh NAME .Sh NAME
@ -90,7 +90,7 @@ noticable smaller than the output for
.Ar chm . .Ar chm .
.It Sy bdz .It Sy bdz
This results in a non-order preserving minimal perfect hash function. This results in a non-order preserving minimal perfect hash function.
Output size is approximately 2.85 bit per key for the default value of Output size is approximately 2.79 bit per key for the default value of
.Ar utilisation , .Ar utilisation ,
1.24. 1.24.
This is also the smallest supported value. This is also the smallest supported value.