Several important system calls Name of Function system call Fork Create a new process Clone Create a child process according to specific conditions
Getpid Obtain the id of a process Fcntl File control Read Read file Write Write file Ioctl Master control function of I/O Table 2.
Many system calls, for example
getpid (), are always performed on the processe's current node and have no remote performance degradation.
The microbenchmark results present the user-perceived run times (measured as wall-clock times) for the open, close, stat, read, write, and getpid system calls.
The standard deviation for the five runs was below 2% for all tests, except for getpid, for which the standard deviation was at most 6%.
Basic naming was provided by a special purpose
GetPid function which mapped logical process identifiers to actual process identifiers using broadcast.sup.4.
As DTSTM needs to intercept system calls, the performance overhead of getpid test program is relatively high.
Samples for application program test Item Command Getpid getpid-2000.sh Decompression tar zxf linux-source.tar.bz2 Compression tar zcf linux-source File Copy cp /usr/linux-source /linux-source Kernel Build make Linux Boot Linux boot