[LU-6134] lfs find --size opens everything

Duplicate — Wed, 5 Aug 2020 21:57:57 +0000

q:lustre-release# git describe
2.6.92-55-g2bc5bcb
q:lustre-release# unset MDSCOUNT
q:lustre-release# llmount.sh
...
q:lustre-release# cd /mnt/lustre
q:lustre# mkdir d0
q:lustre# touch d0/f{0..1023}
q:lustre# strace -o /tmp/1 lfs find --size +4K .
./d0
q:lustre-release# awk -F'(' '{ print $1; }' /tmp/1 | sort | uniq -c
      1 access
      1 arch_prctl
      3 brk
   1034 close
      1 execve
      1 exit_group
      1 fcntl
      8 fstat
      4 getdents
      1 gettimeofday
   3077 ioctl
   1024 lstat
     20 mmap
      9 mprotect
      2 munmap
   1034 open
      6 read
      1 write
q:lustre-release# grep ioctl /tmp/1 | sort | uniq -c
      1 ioctl(3, 0x800466af, 0x7ffff9778e00)    = 0
      1 ioctl(3, 0xc0086683, 0x7ffff9778890)    = 0
      1 ioctl(3, 0xc0086917, 0x2354040)         = 0
      1 ioctl(4, 0x800466af, 0x7ffff9778e00)    = 0
   1024 ioctl(4, 0xc00866a5, 0x2354040)         = 0 # IOC_LOV_GETINFO
   1024 ioctl(4, 0xc0086916, 0x2354040)         = 0 # IOC_MDC_GETFILEINFO
      1 ioctl(4, 0xc0086917, 0x2354040)         = 0 # LL_IOC_MDC_GETINFO
   1024 ioctl(5, 0x800466af, 0x7ffff9778e00)    = 0 # LL_IOC_GET_MDTIDX

For each file returned by getdents on d0 we do:

ioctl(4, 0xc0086916, 0x2354040)         = 0 # IOC_MDC_GETFILEINFO
lstat("./d0/f831", {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
open("./d0/f831", O_RDONLY)             = 5
ioctl(5, 0x800466af, 0x7ffff9778e00)    = 0 # LL_IOC_GET_MDTIDX
close(5)                                = 0
ioctl(4, 0xc00866a5, 0x2354040)         = 0 # IOC_LOV_GETINFO

Whamcloud Community JIRA

[LU-6134] lfs find --size opens everything