On 12/03/2014 11:48 AM, Karthick Srinivasachary wrote:
Hi Folks,
I have question. Any feedback appreciated..!
With buffer_compress_percentage, fio writes random data + zeros.
Is there a way to write random data + repeat_pattern (instead of
zero's). Pattern can be any user given pattern.
We can just make it fill with buffer_pattern instead of zeroing. Given
that the pattern is short enough, it should not skew the compression
rate significantly.
OK, did a quick patch and ran a quick test, looks like it's still within
half a percent.
Pull the latest -git, then apply the attached patch. That should do what
you want. Please report back.
--
Jens Axboe
diff --git a/init.c b/init.c
index 4f66759b59b5..82371044c1f5 100644
--- a/init.c
+++ b/init.c
@@ -724,7 +724,8 @@ static int fixup_options(struct thread_data *td)
if (td->o.compress_percentage == 100) {
td->o.zero_buffers = 1;
td->o.compress_percentage = 0;
- }
+ } else if (td->o.compress_percentage)
+ td->o.refill_buffers = 1;
/*
* Using a non-uniform random distribution excludes usage of
diff --git a/io_u.c b/io_u.c
index 33c82f2c4e9e..963e8cb764b9 100644
--- a/io_u.c
+++ b/io_u.c
@@ -1859,9 +1859,9 @@ static void save_buf_state(struct thread_data *td, struct frand_state *rs)
void fill_io_buffer(struct thread_data *td, void *buf, unsigned int min_write,
unsigned int max_bs)
{
- if (td->o.buffer_pattern_bytes)
- fill_buffer_pattern(td, buf, max_bs);
- else if (!td->o.zero_buffers) {
+ struct thread_options *o = &td->o;
+
+ if (o->compress_percentage && !o->zero_buffers) {
unsigned int perc = td->o.compress_percentage;
struct frand_state *rs;
unsigned int left = max_bs;
@@ -1879,7 +1879,8 @@ void fill_io_buffer(struct thread_data *td, void *buf, unsigned int min_write,
seg = min_write;
fill_random_buf_percentage(rs, buf, perc, seg,
- min_write);
+ min_write, o->buffer_pattern,
+ o->buffer_pattern_bytes);
} else
fill_random_buf(rs, buf, min_write);
@@ -1887,7 +1888,9 @@ void fill_io_buffer(struct thread_data *td, void *buf, unsigned int min_write,
left -= min_write;
save_buf_state(td, rs);
} while (left);
- } else
+ } else if (o->buffer_pattern_bytes && !o->zero_buffers)
+ fill_buffer_pattern(td, buf, max_bs);
+ else
memset(buf, 0, max_bs);
}
diff --git a/lib/rand.c b/lib/rand.c
index a79fb9c17c32..5235c7f5b3f2 100644
--- a/lib/rand.c
+++ b/lib/rand.c
@@ -34,6 +34,7 @@
*/
#include <string.h>
+#include <assert.h>
#include "rand.h"
#include "../hash.h"
@@ -90,15 +91,45 @@ unsigned long fill_random_buf(struct frand_state *fs, void *buf,
return r;
}
+void fill_pattern(void *p, unsigned int len, char *pattern,
+ unsigned int pattern_bytes)
+{
+ switch (pattern_bytes) {
+ case 0:
+ assert(0);
+ break;
+ case 1:
+ memset(p, pattern[0], len);
+ break;
+ default: {
+ unsigned int i = 0, size = 0;
+ unsigned char *b = p;
+
+ while (i < len) {
+ size = pattern_bytes;
+ if (size > (len - i))
+ size = len - i;
+ memcpy(b+i, pattern, size);
+ i += size;
+ }
+ break;
+ }
+ }
+}
+
unsigned long fill_random_buf_percentage(struct frand_state *fs, void *buf,
unsigned int percentage,
- unsigned int segment, unsigned int len)
+ unsigned int segment, unsigned int len,
+ char *pattern, unsigned int pbytes)
{
unsigned long r = __rand(fs);
unsigned int this_len;
if (percentage == 100) {
- memset(buf, 0, len);
+ if (pattern)
+ fill_pattern(buf, len, pattern, pbytes);
+ else
+ memset(buf, 0, len);
return 0;
}
@@ -124,7 +155,10 @@ unsigned long fill_random_buf_percentage(struct frand_state *fs, void *buf,
if (this_len > len)
this_len = len;
- memset(buf, 0, this_len);
+ if (pattern)
+ fill_pattern(buf, this_len, pattern, pbytes);
+ else
+ memset(buf, 0, this_len);
len -= this_len;
buf += this_len;
}
diff --git a/lib/rand.h b/lib/rand.h
index 8c35ab1fa263..803bea484757 100644
--- a/lib/rand.h
+++ b/lib/rand.h
@@ -30,6 +30,7 @@ extern void init_rand(struct frand_state *);
extern void init_rand_seed(struct frand_state *, unsigned int seed);
extern void __fill_random_buf(void *buf, unsigned int len, unsigned long seed);
extern unsigned long fill_random_buf(struct frand_state *, void *buf, unsigned int len);
-extern unsigned long fill_random_buf_percentage(struct frand_state *, void *buf, unsigned int percentage, unsigned int segment, unsigned int len);
+extern unsigned long fill_random_buf_percentage(struct frand_state *, void *, unsigned int, unsigned int, unsigned int, char *, unsigned int);
+extern void fill_pattern(void *p, unsigned int len, char *pattern, unsigned int pattern_bytes);
#endif
diff --git a/verify.c b/verify.c
index c2b3c40edef8..c1791fc69743 100644
--- a/verify.c
+++ b/verify.c
@@ -29,36 +29,6 @@ static void populate_hdr(struct thread_data *td, struct io_u *io_u,
struct verify_header *hdr, unsigned int header_num,
unsigned int header_len);
-static void fill_pattern(void *p, unsigned int len, char *pattern,
- unsigned int pattern_bytes)
-{
- switch (pattern_bytes) {
- case 0:
- assert(0);
- break;
- case 1:
- dprint(FD_VERIFY, "fill verify pattern b=0 len=%u\n", len);
- memset(p, pattern[0], len);
- break;
- default: {
- unsigned int i = 0, size = 0;
- unsigned char *b = p;
-
- dprint(FD_VERIFY, "fill verify pattern b=%d len=%u\n",
- pattern_bytes, len);
-
- while (i < len) {
- size = pattern_bytes;
- if (size > (len - i))
- size = len - i;
- memcpy(b+i, pattern, size);
- i += size;
- }
- break;
- }
- }
-}
-
void fill_buffer_pattern(struct thread_data *td, void *p, unsigned int len)
{
fill_pattern(p, len, td->o.buffer_pattern, td->o.buffer_pattern_bytes);
