>Number:         17929
>Category:       kern
>Synopsis:       mkdir takes > 40 s to complete on a 60 GB disk
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Aug 13 08:58:00 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Lex Wennmacher
>Release:        NetBSD 1.5.3
>Organization:
	
>Environment:
	
	
System: NetBSD cassius.geo.Uni-Koeln.DE 1.5.3 NetBSD 1.5.3 (IGM) #0: Fri Aug 9 14:17:25 MEST 2002 root@cassius.geo.Uni-Koeln.DE:/usr/src/sys/arch/i386/compile/IGM i386
Architecture: i386
Machine: i386
>Description:
	
Filesystem on /dev/wd2d (entire disk, mounted at /d1) is on the following disk:
Aug  9 14:36:50 cassius /netbsd: wd2 at pciide0 channel 1 drive 1: <Maxtor 4W060 H4>
Aug  9 14:36:50 cassius /netbsd: wd2: drive supports 16-sector pio transfers, lba addressing
Aug  9 14:36:50 cassius /netbsd: wd2: 58644 MB, 16383 cyl, 16 head, 63 sec, 512 bytes/sect x 120103200 sectors
Aug  9 14:36:50 cassius /netbsd: wd2: 32-bit data port
Aug  9 14:36:50 cassius /netbsd: wd2: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 5 

The filesystem was created with newfs on 1.5.2, but left empty.
Under NetBSD-1.5.3, data were written to the filesystem, using 'tar'.
Once the disk is ca. 80 % full, the times for mkdir (not on top-level,
in a subdirectory) increase drastically:

% df -ki /d1
Filesystem  1K-blocks     Used    Avail Capacity iused   ifree  %iused  Mounted on
/dev/wd2d    58085459 45809408  9371778    83%    4332 14770514     0%   /d1

% pwd
/d1/wennmach

% time mkdir test
0.0u 0.2s 0:40.51 0.6% 0+0k 5847+6io 0pf+0w 

Note the > 40 s elapsed time and the enormous 5847+6io value.

Writing data to the disk is fast:

% time cp /netbsd . 
0.0u 0.0s 0:00.01 100.0% 0+0k 0+177io 0pf+0w

% ls -s netbsd 
1544 netbsd

Creating directories on the top-level is fast, too:

# pwd
/d1

# time mkdir test1
0.0u 0.0s 0:00.01 0.0% 0+0k 3+4io 0pf+0w
# time mkdir test2
0.0u 0.0s 0:00.02 0.0% 0+0k 2+5io 0pf+0w
# time mkdir test3
0.0u 0.0s 0:00.01 0.0% 0+0k 2+5io 0pf+0w

A dumpfs (size: 2.7 MB) of the file system /d1 is available at:
ftp://gutemine.geo.Uni-Koeln.DE/pub/NetBSD/d1-dumpfs

>How-To-Repeat:
	
see above.

>Fix:
	
Unknown. Probably a problem with ffs_dirpref().

>Release-Note:
>Audit-Trail:
>Unformatted: