File creation and removal in LFS and ext3

In this experiment, we have compared metadata performance of LFS (with roll-forward recovery) and ext3 (with hash b-tree directories) by creating and then deleting half a million files of different sizes. The script which was used to generate the data is available here. The output from this script is shown below. It is again probably worth noting that LFS incurred no cleaning overhead in these tests.

The computer used in this experiment was an AMD Athlon(tm) XP 2500+ with 256MB RAM with two SATA disks. The measured file systems always resided on a 80GB Seagate Barracuda while the rest of the system was placed on a 120GB WD.

Script output for LFS (dd output and similar things excluded):

	  Creating 500000 empty files

	  real	4m47.760s
	  user	1m37.414s
	  sys	3m7.716s
	  Done

	  Remounting

	  Deleting 500000 files of size 0 bytes

	  real	5m36.297s
	  user	1m40.410s
	  sys	3m12.924s
	  Done

	  Remounting

	  Creating 500000 files of size 4096 bytes

	  real	6m47.779s
	  user	2m12.028s
	  sys	3m39.158s
	  Done

	  Remounting

	  Deleting 500000 files of size 4096 bytes

	  real	6m7.173s
	  user	1m44.787s
	  sys	3m26.317s
	  Done

	  Remounting

	  Creating 500000 files of size 16384 bytes

	  real	11m31.638s
	  user	2m18.433s
	  sys	4m3.207s
	  Done

	  Remounting

	  Deleting 500000 files of size 16384 bytes

	  real	6m44.313s
	  user	1m45.163s
	  sys	3m28.461s

	  Remounting

	  Creating 500000 files of size 65536 bytes

	  real    22m35.518s
	  user    2m37.826s
	  sys     5m17.376s
	  Done

	  Remounting

	  Deleting 500000 files of size 65536 bytes

	  real    7m22.606s
	  user    1m44.667s
	  sys     3m22.337s

	  Done
	

Script output for ext3 (dd output and similar things excluded):

	  Creating 500000 empty files

	  real	5m14.915s
	  user	1m35.830s
	  sys	3m9.700s
	  Done

	  Remounting

	  Deleting 500000 files of size 0 bytes

	  real	7m4.185s
	  user	1m38.130s
	  sys	3m13.132s
	  Done

	  Remounting

	  Creating 500000 files of size 4096 bytes

	  real	10m57.699s
	  user	2m11.224s
	  sys	3m55.075s
	  Done

	  Remounting

	  Deleting 500000 files of size 4096 bytes

	  real	7m19.086s
	  user	1m39.846s
	  sys	3m25.337s
	  Done

	  Remounting

	  Creating 500000 files of size 16384 bytes

	  real	9m44.170s
	  user	2m20.889s
	  sys	4m29.633s
	  Done

	  Remounting

	  Deleting 500000 files of size 16384 bytes

	  real	7m13.020s
	  user	1m37.518s
	  sys	3m20.681s

	  Remounting 

	  Creating 500000 files of size 65536 bytes

	  real    47m40.139s
	  user    2m45.786s
	  sys     6m40.061s
	  Done
	  Remounting
	  Deleting 500000 files of size 65536 bytes
	  
	  real    20m35.223s
	  user    1m39.418s
	  sys     3m50.514s
	  
	  Done