[Lustre-discuss] Not updated mtime after editted

[Satoshi Isono]

Dear members,

I got the strange output on mtime information. Does anyone have such experiences?
Could you try to do this test, please?
My Lustre environment is that client: 1.6.5.1-2.6.18_53.1.6.el5 and 
OSS: 1.6.6.-2.6.18_92.1.10.el5.

Only such case of echo "">> mv_test.txt does NOT update mtime. touch 
command and new creation with echo command is OK. And, in case of 
adding the time using sleep command, it also is OK.

$ cat check.sh

   1 #!/bin/sh
   2
   3 echo "## START ORIGINAL TIME STAMP"
   4 cp -p mv_test.txt.org mv_test.txt
   5 #cp mv_test.txt.org mv_test.txt
   6 ls -i --full-time mv_test.txt*| awk '{print $10"\t"$1"\t"$7" "$8}'
   7 #stat mv_test.txt*
   8
   9 echo "## REVISE mv_test.txt"
  10 #sleep 1
  11 #touch mv_test.txt
  12 echo "">> mv_test.txt
  13 #echo ""> mv_test.txt
  14
  15 echo "## CHECK TIME STAMP"
  16 ls -i --full-time mv_test.txt*| awk '{print $10"\t"$1"\t"$7" "$8}'
  17
  18 #rm mv_test.txt.org
  19 COUNT=0
  20
  21 for i in `seq 1 2`
  22 do
  23
  24    COUNT=`expr $COUNT + 1`
  25
  26 #   touch mv_test.txt
  27    mv mv_test.txt mv_test.txt.mv
  28
  29    echo "No.$COUNT"
  30    ls -i --full-time mv_test.txt*| awk '{print $10"\t"$1"\t"$7" "$8}'
  31
  32    mv mv_test.txt.mv mv_test.txt
  33
  34    COUNT=`expr $COUNT + 1`
  35
  36    echo "No.$COUNT"
  37    ls -i --full-time mv_test.txt*| awk '{print $10"\t"$1"\t"$7" "$8}'
  38 #   stat mv_test.txt*
  39
  40 done

Regards,
Satoshi Isono