ext2fs "performace"

Harald Koenig (koenig@tat.physik.uni-tuebingen.de)
Thu, 20 Jun 1996 12:00:43 +0200 (MET DST)


Hi,

running Linux-2.0.0 on a 83 MHz Pentium OverDrive with fast SCSI disk
using a 2.6 GB ext2fs partition with only two files with 1GB size each
I removed these files. removing only one file took 100 seconds real time !!

I've tried this again then by just creating a big file of zeros to get
some timing data:

# time dd if=/dev/zero bs=1024k count=1100 of=/mnt/BIG.1
6:12.71 real, 0.07 user, 343.83 sys, 92% cpu
# sync
# time rm /mnt/BIG.1 ; time sync
1:37.99 real, 0.00 user, 4.94 sys, 5% cpu
0:03.25 real, 0.00 user, 0.43 sys, 13% cpu

in writing the file CPU and memory bandwidth seem to be the bottleneck
(32 bit DRAM in ASUS SP3G board; 486 Saturn chipset; disk has >= 7MB/sec
formatted media transfer rate connected to fast/sync NCR 53C810).

but why does removing this file takes so much time ?
that's only a "removage rate" of ~11 MB/sec :-(

Harald

-- 
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