Just thought I'd share some test results of mine in case anyone is interested.
Basically the tests are siumulating what our product does with files - although the tests do it a lot quicker (not as many files though).
The test is to create 1 million files (each containing the text of the file number) spread over a number of directories. The files are then removed in the same manner as they are created. I added tests later to overwrite the existing files to see if there is any additional performance hit.
All results in seconds, in kernel order 2.4.20 (pre11), 2.4.21, 2.4.21 + dir_index
Files spread over 100 directories:
Create : 1764, N/A, 1078
Remove : 611, N/A, 1310
Ok so results are not that great - better to use more directories.
Files spread over 1000 directories:
Create: 409, 305, 284
Remove: 138, 96, 141
Create: 377, 312, 276
Overwrite: 317, 246, 268
Overwrite2: 321, 241, 265
I was interested in seeing if the htree patches would give me a performance increase - although I guess the sequential nature of the file creation/deletion probably will not benefit - although I was suprised that adding dir_index hit the overwrite and removal speed - probably based on this testing I won't use this feature (yet).
Cpu info:
processor : 0
vendor_id : AuthenticAMD
cpu family : 6
model
: 3
model name : AMD Duron(tm) Processor
stepping : 1
cpu MHz : 1016.400
cache size : 64 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu
: yes
fpu_exception : yes
cpuid level : 1
wp
: yes
flags
: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36
mmx fxsr syscall mmxext 3dnowext 3dnow
bogomips : 2025.06
hdparm -i /dev/hda
/dev/hda:
Model=Maxtor 6Y080L0, FwRev=YAR41BW0, SerialNo=Y2M0FH0E
Config={ Fixed }
RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=57
BuffType=3(DualPortCache), BuffSize=2048kB, MaxMultSect=16,
MultSect=16
DblWordIO=no, OldPIO=2, DMA=yes, OldDMA=0
CurCHS=4047/16/255, CurSects=-217054981, LBA=yes, LBAsects=160086528
tDMA={min:120,rec:120}, DMA modes: mword0 mword1 mword2
IORDY=on/off, tPIO={min:120,w/IORDY:120}, PIO modes: mode3
mode4
UDMA modes: mode0 mode1 mode2 mode3 mode4 *mode5 mode6
[ct_sys@installed TEST]# hdparm /dev/hda
/dev/hda:
multcount = 16 (on)
I/O support = 0 (default 16-bit)
unmaskirq = 0 (off)
using_dma = 1 (on)
keepsettings = 0 (off)
nowerr = 0 (off)
readonly = 0 (off)
readahead = 8 (on)
geometry = 9964/255/63, sectors =
160086528, start = 0
Kernel 2.4.20 & 21 both output same disk settings.
Glen
