When it comes to searching for files and patterns in a recursive manner, both grep and find commands can be used. However, depending on the scenario and file system characteristics, one may be more efficient or faster than the other. The following syscall statistics obtained using strace provide insights into the performance comparison of grep and find in recursive mode.
Find Command:
Using the find command with the -exec option to execute grep recursively:
strace -cf find . -type f -exec grep -i -r 'system' {} \;
The syscall statistics obtained are as follows:
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
65.21 0.286153 2778 103 wait4
5.21 0.022875 16 1475 mmap
4.83 0.021184 17 1250 close
3.42 0.015023 21 702 fcntl
3.41 0.014954 18 838 mprotect
3.25 0.014260 15 921 fstat
2.51 0.011033 17 643 open
1.95 0.008549 16 526 read
... (remaining syscall statistics)
Grep Command:
Using the grep command with the -r and -i options to perform recursive case-insensitive searching:
strace -cf grep -r -i 'system' .
The obtained syscall statistics for the grep command are as follows:
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
25.61 0.009470 17 550 fcntl
13.45 0.004974 18 271 close
11.53 0.004264 23 184 openat
10.54 0.003898 19 210 read
9.12 0.003372 17 193 fstat
8.93 0.003301 21 156 getdents
... (remaining syscall statistics)
These statistics provide insights into the system calls made by each command during the execution of the recursive search. It’s important to note that the actual performance can vary depending on various factors such as the size and structure of the file system, the number of files and directories, disk speed, and CPU capabilities.
In some scenarios, using find to locate files and then executing grep on each file may provide better performance, especially when dealing with many small files. This approach allows reading a large number of file entries and inodes at once, potentially benefiting from performance improvements on rotating media.
It’s recommended to consider the specific requirements and characteristics of the task at hand and conduct performance tests with representative data to determine which approach is more efficient or faster in a given context.