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3 months ago
/*
* An experiment with parallel reading and writing of files.
*
* (c) 2007 Martin Mares <mj@ucw.cz>
*/
#include <ucw/lib.h>
#include <ucw/conf.h>
#include <ucw/io.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#define COPY
#define DIRECT 0 // or O_DIRECT
static timestamp_t timer;
#define P_INIT do { cnt = 0; cnt_rep = 0; cnt_ms = 1; } while(0)
#define P_UPDATE(cc) do { \
cnt += cc; \
if (cnt >= cnt_rep) { cnt_ms += get_timer(&timer); \
printf("%d of %d MB (%.2f MB/sec)\r", (int)(cnt >> 20), (int)(total_size >> 20), (double)cnt / 1048576 * 1000 / cnt_ms); \
fflush(stdout); cnt_rep += 1<<26; } } while(0)
#define P_FINAL do { \
cnt_ms += get_timer(&timer); \
msg(L_INFO, "Spent %.3f sec (%.2f MB/sec)", (double)cnt_ms/1000, (double)cnt / 1048576 * 1000 / cnt_ms); \
} while(0)
int main(int argc, char **argv)
{
uint files, bufsize;
u64 total_size;
if (argc != 4 ||
cf_parse_int(argv[1], (int*) &files) ||
cf_parse_int(argv[2], (int*) &bufsize) ||
cf_parse_u64(argv[3], &total_size))
{
fprintf(stderr, "Usage: file-test <nr-files> <bufsize> <totalsize>\n");
return 1;
}
u64 cnt, cnt_rep;
uint cnt_ms;
int fd[files];
byte *buf[files], name[files][16];
uint xbufsize = bufsize; // Used for single-file I/O
byte *xbuf = big_alloc(xbufsize);
init_timer(&timer);
#ifdef COPY
msg(L_INFO, "Creating input file");
int in_fd = ucw_open("tmp/ft-in", O_RDWR | O_CREAT | O_TRUNC | DIRECT, 0666);
ASSERT(in_fd >= 0);
ASSERT(!(total_size % xbufsize));
P_INIT;
for (uint i=0; i<total_size/xbufsize; i++)
{
for (uint j=0; j<xbufsize; j++)
xbuf[j] = i+j;
uint c = write(in_fd, xbuf, xbufsize);
ASSERT(c == xbufsize);
P_UPDATE(c);
}
lseek(in_fd, 0, SEEK_SET);
sync();
P_FINAL;
#endif
msg(L_INFO, "Initializing output files");
for (uint i=0; i<files; i++)
{
sprintf(name[i], "tmp/ft-%d", i);
fd[i] = ucw_open(name[i], O_RDWR | O_CREAT | O_TRUNC | DIRECT, 0666);
if (fd[i] < 0)
die("Cannot create %s: %m", name[i]);
buf[i] = big_alloc(bufsize);
}
sync();
get_timer(&timer);
msg(L_INFO, "Writing %d MB to %d files in parallel with %d byte buffers", (int)(total_size >> 20), files, bufsize);
P_INIT;
for (uint r=0; r<total_size/bufsize/files; r++)
{
for (uint i=0; i<files; i++)
{
#ifdef COPY
uint ci = read(in_fd, buf[i], bufsize);
ASSERT(ci == bufsize);
#else
for (uint j=0; j<bufsize; j++)
buf[i][j] = r+i+j;
#endif
uint c = write(fd[i], buf[i], bufsize);
ASSERT(c == bufsize);
P_UPDATE(c);
}
}
#ifdef COPY
close(in_fd);
#endif
msg(L_INFO, "Syncing");
sync();
P_FINAL;
msg(L_INFO, "Reading the files sequentially");
P_INIT;
for (uint i=0; i<files; i++)
{
lseek(fd[i], 0, SEEK_SET);
for (uint r=0; r<total_size/xbufsize/files; r++)
{
uint c = read(fd[i], xbuf, xbufsize);
ASSERT(c == xbufsize);
P_UPDATE(c);
}
close(fd[i]);
}
P_FINAL;
for (uint i=0; i<files; i++)
unlink(name[i]);
#ifdef COPY
unlink("tmp/ft-in");
#endif
msg(L_INFO, "Done");
return 0;
}