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int gettimeofday(struct
timeval *tv, struct timezone *tz);
int settimeofday(const
struct timeval *tv , const struct timezone *tz);
struct timeval {
time_t tv_sec; /* seconds */
suseconds_t tv_usec; /*
microseconds */
};
struct timezone {
int tz_minuteswest; /* minutes
west of Greenwich
*/
int
tz_dsttime; /* type of DST
correction */
};
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…
struct timeval
t_start,t_end;
long cost_time = 0;
//get start
time
gettimeofday(&t_start,
NULL);
printf("Start
time: %ld us", t_start.tv_usec);
//some
operation
…
//get end time
gettimeofday(&t_end,
NULL);
printf("End
time: %ld us", t_end.tv_usec);
//calculate
time slot
cost_time =
t_end.tv_usec - t_start.tv_usec;
printf("Cost
time: %ld us", cost_time);
…
Êä³ö£º
Start time:
438061 us
End time:
459867 us
Cost time:
21806 us
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install
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struct timeval
{
time_t tv_sec; /***second***/
susecond_t tv_usec;/***microsecond***/
}
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free_bootmem()Õâ¸öº¯ÊýÊÇϵͳÆô¶¯³õÆÚÄÚ´æÊͷŵĺËÐĺ¯Êý£¬ÎÒÃÇÀ´¿´¿´ËüµÄ´úÂë¡£
void __init free_bootmem (unsigned long addr, unsigned long size)//addrÊÇÒªÊͷŵÄÎïÀíÆðʼµØÖ·£¬sizeÊÇÒªÊÍ·Å¿Õ¼äµÄ´óС¡£
{
free_bootmem_core(NODE_DATA(0)->bdata, addr, size);//Ö±½ ......
Name
hosts - The static table lookup for host names
Synopsis
/etc/hosts
Description
This manual page describes the format of the /etc/hosts
file. This file is a simple text file that
associates IP addresses with hostnames, one line per IP address. For
each host a single line should be presen ......
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[root@local]# vmstat 2
procs -----------memory---------- ---swap-- -----io-- ......