long delay in sending mail

[Brian Bucher <babucher_(_at_)_alum_(_dot_)_mit_(_dot_)_edu>]

Greetings,

Having been pleased with the performance of my openbsd server so far, I have
a question about a delay I'm getting when sending email.  The clients are
windows boxes using either Eudora or Outlook for email.  Checking email
is very fast...as in less than a second between the time I hit the
check new mail / receive mail button and when it begins to download the
email.  However, when attempting to send mail, there's often a multiple-
minute delay before the server accepts the request to send mail.

In addition, sshing to the server can take several minutes before receiving
a login prompt.  What is strange to me is the following 'top' information.
I would expect to see something besides just a 2% interrupt, so I'm thinking
the problem lies therein, but I do not know how to troubleshoot it.  Could
this be a hardware problem?  Perhaps writing to the disk (new email outgoing)
cannot perform as fast as simply reading from the disk (checking email)?

Whoa, I just did a dmesg to append to the email, and there appears to be some
stuff I can only classify as bogus.  I don't know if that has anything to do
with the interrupt problem though.

Any and all help would be appreciated.

Thanks,
Brian


Example top output shown below.
The interrupt value varies between about 2% and 0, while every once in a
while either the user value or system value will show 0.2%.
uz1 is my login


load 
averages:  0.12,  0.14,  0.11                                       16:08:19
20 processes:  1 running, 19 idle
CPU states:  0.0% user,  0.0% nice,  0.0% system,  2.0% interrupt, 98.0% idle
Memory: Real: 9232K/24M act/tot  Free: 97M  Swap: 4K/300M used/tot

  PID USERNAME PRI NICE  SIZE   RES STATE WAIT     TIME    CPU COMMAND
10957 named      2    0 2052K 2516K idle  select   1:59  0.00% named
14313 root       2    0  724K 1504K sleep select   1:09  0.00% sendmail
20636 root      10    0  568K 1024K sleep nanosl   1:09  0.00% ipmon
27338 root       2    0  104K  488K sleep select   0:36  0.00% syslogd
24785 root       2    0   80K  556K idle  select   0:17  0.00% inetd
31171 root       2    0  336K 1196K idle  select   0:11  0.00% sshd
 2524 root      10    0  224K  652K sleep nanosl   0:09  0.00% cron
25229 root       2    0   32K  480K idle  netio    0:00  0.00% comsat
15662 root       2    0  364K 1528K sleep select   0:00  0.00% sshd
    1 root      10    0  340K  204K idle  wait     0:00  0.00% init
 7533 root      18    0  328K  252K idle  pause    0:00  0.00% csh
 7446 root      28    0  132K  872K run   -        0:00  0.00% top
32516 uz1       18    0  388K  344K idle  pause    0:00  0.00% ksh
 5226 root      18    0  388K  344K idle  pause    0:00  0.00% sh
10334 root       3    0   44K  628K idle  ttyin    0:00  0.00% getty
31903 root       3    0   44K  588K idle  ttyin    0:00  0.00% getty
31036 root       3    0   44K  588K idle  ttyin    0:00  0.00% getty
15345 root       3    0   44K  588K idle  ttyin    0:00  0.00% getty
22144 root       3    0   44K  588K idle  ttyin    0:00  0.00% getty

# dmesg
OpenBSD 2.9-stable (GENERIC) #0: Fri Jan 25 09:51:36 EST 2002
    bab_(_at_)_fire1:/usr/src/sys/arch/i386/compile/GENERIC
cpu0: Intel Pentium III ("GenuineIntel" 686-class, 512KB L2 cache) 451 MHz
cpu0: 
FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,SYS,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR,
SIMD
real mem  = 133804032 (130668K)
avail mem = 119144448 (116352K)
using 1658 buffers containing 6791168 bytes (6632K) of memory
mainbus0 (root)
bios0 at mainbus0: AT/286+(71) BIOS, date 07/07/99, BIOS32 rev. 0 @ 0xfb380
apm0 at bios0: Power Management spec V1.2
apm0: AC on, battery charge unknown
pcibios0 at bios0: rev. 2.1 @ 0xf0000/0xb7f8
pcibios0: PCI IRQ Routing Table rev. 1.0 @ 0xfde90/112 (5 entries)
pcibios0: bad IRQ table checksum
pcibios0: PCI BIOS has 5 Interrupt Routing table entries
pcibios0: PCI Exclusive IRQs: 5 10 11
pcibios0: PCI bus #1 is the last bus
bios0: ROM list: 0xc0000/0xc000
pci0 at mainbus0 bus 0: configuration mode 1 (no bios)
pchb0 at pci0 dev 0 function 0 "Intel 82443BX PCI-AGP" rev 0x03
ppb0 at pci0 dev 1 function 0 "Intel 82443BX AGP" rev 0x03
pci1 at ppb0 bus 1
vga1 at pci1 dev 0 function 0 "SIS 6326 AGP Video" rev 0xd2
wsdisplay0 at vga1: console (80x25, vt100 emulation)
wsdisplay0: screen 1-5 added (80x25, vt100 emulation)
pcib0 at pci0 dev 7 function 0 "Intel 82371AB PIIX4 ISA" rev 0x02
pciide0 at pci0 dev 7 function 1 "Intel 82371AB IDE" rev 0x01: DMA, channel 
0 wire
d to compatibility, channel 1 wired to compatibility
wd0 at pciide0 channel 0 drive 0: <FUJITSU MPD3130AT>
wd0: 16-sector PIO, LBA, 12417MB, 16383 cyl, 16 head, 63 sec, 25431840 sectors
pciide0: channel 0 interrupting at irq 14
wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 2
uhci0 at pci0 dev 7 function 2 "Intel 82371AB USB" rev 0x01: irq 11
usb0 at uhci0: USB revision 1.0
uhub0 at usb0
uhub0: vendor 0x0000 UHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub0: 2 ports with 2 removable, self powered
"Intel 82371AB Power Management" rev 0x02 at pci0 dev 7 function 3 not 
configured
xl0 at pci0 dev 9 function 0 "3Com 3c905B 100Base-TX" rev 0x30: irq 10 
address 00:
01:02:72:1b:87
exphy0 at xl0 phy 24: 3Com internal media interface
xl1 at pci0 dev 11 function 0 "3Com 3c905B 100Base-TX" rev 0x30: irq 5 
address 00:
01:02:ec:4b:76
exphy1 at xl1 phy 24: 3Com internal media interface
isa0 at pcib0
isadma0 at isa0
pckbc0 at isa0 port 0x60/5
pckbd0 at pckbc0 (kbd slot)
pckbc0: using irq 1 for kbd slot
wskbd0 at pckbd0: console keyboard, using wsdisplay0
pms0 at pckbc0 (aux slot)
pckbc0: using irq 12 for aux slot
wsmouse0 at pms0 mux 0
pcppi0 at isa0 port 0x61
midi0 at pcppi0: <PC speaker>
sysbeep0 at pcppi0
lpt0 at isa0 port 0x378/4 irq 7
npx0 at isa0 port 0xf0/16: using exception 16
pccom0 at isa0 port 0x3f8/8 irq 4: ns16550a, 16 byte fifo
pccom1 at isa0 port 0x2f8/8 irq 3: ns16550a, 16 byte fifo
fdc0 at isa0 port 0x3f0/6 irq 6 drq 2
fd0 at fdc0 drive 0: 1.44MB 80 cyl, 2 head, 18 sec
biomask 4840 netmask 4c60 ttymask 5ce2
pctr: 686-class user-level performance counters enabled
mtrr: Pentium Pro MTRR support
dkcsum: wd0 matched BIOS disk 80
root on wd0a
rootdev=0x0 rrootdev=0x300 rawdev=0x302
wd0(pciide0:0:0): timeout
        type: ata
        c_bcount: 8192
        c_skip: 0
pciide0:0:0: bus-master DMA error: missing interrupt, status=0x21
wd0a: DMA error reading fsbn 64 of 64-79 (wd0 bn 127; cn 0 tn 2 sn 1), retrying
wd0: soft error (corrected)
wd0(pciide0:0:0): timeout
        type: ata
        c_bcount: 8192
        c_skip: 0
pciide0:0:0: bus-master DMA error: missing interrupt, status=0x21
wd0a: DMA error reading fsbn 80 of 80-95 (wd0 bn 143; cn 0 tn 2 sn 17), 
retrying
wd0: soft error (corrected)
wd0(pciide0:0:0): timeout
        type: ata
        c_bcount: 8192
        c_skip: 0
pciide0:0:0: bus-master DMA error: missing interrupt, status=0x21
wd0a: DMA error reading fsbn 64 of 64-79 (wd0 bn 127; cn 0 tn 2 sn 1), retrying
wd0: soft error (corrected)
wd0(pciide0:0:0): timeout
        type: ata
        c_bcount: 8192
        c_skip: 0
pciide0:0:0: bus-master DMA error: missing interrupt, status=0x21
wd0a: DMA error reading fsbn 80 of 80-95 (wd0 bn 143; cn 0 tn 2 sn 17), 
retrying
wd0: soft error (corrected)
wd0(pciide0:0:0): timeout
        type: ata
        c_bcount: 8192
        c_skip: 0
pciide0:0:0: bus-master DMA error: missing interrupt, status=0x21
wd0a: DMA error reading fsbn 80 of 80-95 (wd0 bn 143; cn 0 tn 2 sn 17), 
retrying
wd0: soft error (corrected)
wd0(pciide0:0:0): timeout
        type: ata
        c_bcount: 8192
        c_skip: 0
pciide0:0:0: bus-master DMA error: missing interrupt, status=0x21
wd0a: DMA error reading fsbn 64 of 64-79 (wd0 bn 127; cn 0 tn 2 sn 1), retrying
wd0: soft error (corrected)
wd0(pciide0:0:0): timeout
        type: ata
        c_bcount: 8192
        c_skip: 0
pciide0:0:0: bus-master DMA error: missing interrupt, status=0x21
wd0a: DMA error reading fsbn 80 of 80-95 (wd0 bn 143; cn 0 tn 2 sn 17), 
retrying
wd0: soft error (corrected)
#