3 ms·

I tried quickly looking into this to verify the claim, but haven't yet found anything to explain why this would be the case. Do you have any details about how

I tried quickly looking into this to verify the claim, but haven't yet found anything to explain why this would be the case. Do you have any details about how or why git will scan everything in this case? I did find a pretty neat stack overflow post on the subject of gitignore whitelisting [0]. If we can get to the bottom of possible performance impact, would be cool to add the info there. [0] https://stackoverflow.com/a/15320746/293064 https://stackoverflow.com/a/15320746/293064

minaguib 8y ago
Without spending too much time on it, I think a cursory check shows git doing "the smart thing" with ignore rules. $ mkdir foo $ cd foo $ mkdir $(seq 1 1000) $ git init . $ strace -c git status On branch master No commits yet nothing to commit (create/copy files and use "git add" to track) % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 75.97 0.058830 57 1035 15 openat 16.48 0.012764 6 2002 getdents 3.87 0.002999 3 1021 close 2.91 0.002254 2 1022 fstat 0.19 0.000147 8 18 14 lstat 0.13 0.000100 4 24 read 0.12 0.000092 6 16 12 stat 0.09 0.000072 3 21 14 access 0.06 0.000048 10 5 write 0.04 0.000033 33 1 unlink 0.03 0.000020 3 8 rt_sigaction 0.02 0.000018 2 12 mprotect 0.02 0.000015 15 1 munmap 0.01 0.000010 3 4 getcwd 0.01 0.000006 0 16 mmap 0.01 0.000006 6 1 ioctl 0.01 0.000005 2 3 brk 0.01 0.000004 4 1 chdir 0.00 0.000003 2 2 getpid 0.00 0.000003 3 1 1 readlink 0.00 0.000002 1 2 rt_sigprocmask 0.00 0.000002 2 1 set_tid_address 0.00 0.000002 2 1 set_robust_list 0.00 0.000002 2 1 prlimit64 0.00 0.000000 0 1 execve 0.00 0.000000 0 1 arch_prctl ------ ----------- ----------- --------- --------- ---------------- 100.00 0.077437 5221 56 total Now let's add an ignore-all and check: $ echo "/*" > .gitignore $ strace -c git status On branch master No commits yet nothing to commit (create/copy files and use "git add" to track) % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 46.25 0.000568 284 2 getdents 16.78 0.000206 6 35 14 openat 7.41 0.000091 6 16 12 stat 7.17 0.000088 4 21 14 access 5.62 0.000069 3 25 read 4.72 0.000058 3 18 14 lstat 4.15 0.000051 2 22 close 2.93 0.000036 36 1 unlink 2.28 0.000028 1 23 fstat 0.81 0.000010 3 4 getcwd 0.65 0.000008 1 8 rt_sigaction 0.41 0.000005 5 1 ioctl 0.33 0.000004 4 1 chdir 0.24 0.000003 2 2 getpid 0.24 0.000003 3 1 1 readlink 0.00 0.000000 0 5 write 0.00 0.000000 0 16 mmap 0.00 0.000000 0 12 mprotect 0.00 0.000000 0 1 munmap 0.00 0.000000 0 3 brk 0.00 0.000000 0 2 rt_sigprocmask 0.00 0.000000 0 1 execve 0.00 0.000000 0 1 arch_prctl 0.00 0.000000 0 1 set_tid_address 0.00 0.000000 0 1 set_robust_list 0.00 0.000000 0 1 prlimit64 ------ ----------- ----------- --------- --------- ---------------- 100.00 0.001228 224 55 total

minaguib 8y ago

Without spending too much time on it, I think a cursory check shows git doing "the smart thing" with ignore rules. $ mkdir foo $ cd foo $ mkdir $(seq 1 1000) $ git init . $ strace -c git status On branch master No commits yet nothing to commit (create/copy files and use "git add" to track) % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 75.97 0.058830 57 1035 15 openat 16.48 0.012764 6 2002 getdents 3.87 0.002999 3 1021 close 2.91 0.002254 2 1022 fstat 0.19 0.000147 8 18 14 lstat 0.13 0.000100 4 24 read 0.12 0.000092 6 16 12 stat 0.09 0.000072 3 21 14 access 0.06 0.000048 10 5 write 0.04 0.000033 33 1 unlink 0.03 0.000020 3 8 rt_sigaction 0.02 0.000018 2 12 mprotect 0.02 0.000015 15 1 munmap 0.01 0.000010 3 4 getcwd 0.01 0.000006 0 16 mmap 0.01 0.000006 6 1 ioctl 0.01 0.000005 2 3 brk 0.01 0.000004 4 1 chdir 0.00 0.000003 2 2 getpid 0.00 0.000003 3 1 1 readlink 0.00 0.000002 1 2 rt_sigprocmask 0.00 0.000002 2 1 set_tid_address 0.00 0.000002 2 1 set_robust_list 0.00 0.000002 2 1 prlimit64 0.00 0.000000 0 1 execve 0.00 0.000000 0 1 arch_prctl ------ ----------- ----------- --------- --------- ---------------- 100.00 0.077437 5221 56 total Now let's add an ignore-all and check: $ echo "/*" > .gitignore $ strace -c git status On branch master No commits yet nothing to commit (create/copy files and use "git add" to track) % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 46.25 0.000568 284 2 getdents 16.78 0.000206 6 35 14 openat 7.41 0.000091 6 16 12 stat 7.17 0.000088 4 21 14 access 5.62 0.000069 3 25 read 4.72 0.000058 3 18 14 lstat 4.15 0.000051 2 22 close 2.93 0.000036 36 1 unlink 2.28 0.000028 1 23 fstat 0.81 0.000010 3 4 getcwd 0.65 0.000008 1 8 rt_sigaction 0.41 0.000005 5 1 ioctl 0.33 0.000004 4 1 chdir 0.24 0.000003 2 2 getpid 0.24 0.000003 3 1 1 readlink 0.00 0.000000 0 5 write 0.00 0.000000 0 16 mmap 0.00 0.000000 0 12 mprotect 0.00 0.000000 0 1 munmap 0.00 0.000000 0 3 brk 0.00 0.000000 0 2 rt_sigprocmask 0.00 0.000000 0 1 execve 0.00 0.000000 0 1 arch_prctl 0.00 0.000000 0 1 set_tid_address 0.00 0.000000 0 1 set_robust_list 0.00 0.000000 0 1 prlimit64 ------ ----------- ----------- --------- --------- ---------------- 100.00 0.001228 224 55 total