ну, как-бы вот:
bash-2.05b# sysctl -a | grep hz
kern.clockrate: { hz = 1000, tick = 1000, profhz = 666, stathz = 133 }

сервер, к астериску отношения не имеющий, ядро - generic минус лишние устройста плюс файерволл.

ядро бсд как раз имеет прямое отношение к астериску а еще точнее к факсам
чем медленнеее переключаються контексты тем хуже зетест
(если я правильно понял с соурсов заптела)

сейчас ситуация такова, что вместо сервера стоит мой домашний тазик. как оказалось, этот трехлетний гроб, собранные на VIA KT400, обрабатывает прерывания на порядок лучше, чем свежий типасервер местного производства на TYAN S5197G2NR (хоть мой тазик и сильно уступает в скорости и кол-ве памяти).

сомнительно что проблема в железе
сравните софт
от версий бсд+- тюнинг который делался
до версий астериска драйверов итд
пересобранных с нУлЯ

повторите операцию установки (конфиг)отдельно на двух разных материнках
результаты расскажете

системы АБСОЛЮТНО идентичные (копировалось dump|restore'ом после полной установки всех драйверов, астера и проч).

есть еще одна странность. даже не знаю, как к ней отнестись.

когда я к этому глючноватому серверу подключал слейвом свой домашний компьютер (с астериском) по Е1, то домашний астер выдавал аккуратность - точно 100%. подключил к оператору - точность сразу сильно понизилась.

прям таки загадка
кинте два файла dmesg -a
с этих двух серверов
посмотреть что там за железо у вас

dmesg -a ничего не даст.
вот /var/run/dmesg.boot с компьютера, на котором заптел работает лучше (мой домашний на VIA KT400)
Copyright (c) 1992-2008 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
The Regents of the University of California. All rights reserved.
FreeBSD is a registered trademark of The FreeBSD Foundation.
FreeBSD 7.0-RELEASE #0: Thu Aug 7 11:39:18 EEST 2008
root@asterisk-tmp.niko.local:/usr/obj/usr/src/sys/ASTER
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: AMD Athlon(tm) XP 2500+ (1833.92-MHz 686-class CPU)
Origin = "AuthenticAMD" Id = 0x6a0 Stepping = 0
Features=0x383fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CM OV,PAT,PSE36,MMX,FXSR,SSE>
AMD Features=0xc0400800<SYSCALL,MMX+,3DNow!+,3DNow!>
real memory = 671023104 (639 MB)
avail memory = 642785280 (613 MB)
ACPI APIC Table: <KT400 AWRDACPI>
ioapic0 <Version 0.3> irqs 0-23 on motherboard
kbd1 at kbdmux0
ath_hal: 0.9.20.3 (AR5210, AR5211, AR5212, RF5111, RF5112, RF2413, RF5413)
hptrr: HPT RocketRAID controller driver v1.1 (Aug 7 2008 11:38:51)
acpi0: <KT400 AWRDACPI> on motherboard
acpi0: [ITHREAD]
acpi0: Power Button (fixed)
Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000
acpi_timer0: <24-bit timer at 3.579545MHz> port 0x4008-0x400b on acpi0
cpu0: <ACPI CPU> on acpi0
acpi_button0: <Power Button> on acpi0
acpi_button1: <Sleep Button> on acpi0
pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
pci0: <ACPI PCI bus> on pcib0
agp0: <VIA 8377 (Apollo KT400/KT400A/KT600) host to PCI bridge> on hostb0
agp0: aperture size is 256M
pcib1: <PCI-PCI bridge> at device 1.0 on pci0
pci1: <PCI bus> on pcib1
vgapci0: <VGA-compatible display> mem 0xe8000000-0xe8ffffff,0xd8000000-0xdffffff f,0xe0000000-0xe007ffff irq 16 at device 0.0 on pci1
rl0: <RealTek 8139 10/100BaseTX> port 0xd000-0xd0ff mem 0xea029000-0xea0290ff ir q 20 at device 10.0 on pci0
miibus0: <MII bus> on rl0
rlphy0: <RealTek internal media interface> PHY 0 on miibus0
rlphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
rl0: Ethernet address: 00:e0:4c:00:8c:51
rl0: [ITHREAD]
pci0: <network> at device 12.0 (no driver attached)
dc0: <3Com OfficeConnect 10/100B> port 0xd400-0xd4ff mem 0xea028000-0xea0283ff i rq 23 at device 13.0 on pci0
miibus1: <MII bus> on dc0
ukphy0: <Generic IEEE 802.3u media interface> PHY 1 on miibus1
ukphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
dc0: Ethernet address: 00:0a:48:04:19:c7
dc0: [ITHREAD]
uhci0: <VIA 83C572 USB controller> port 0xd800-0xd81f irq 21 at device 16.0 on p ci0
uhci0: [GIANT-LOCKED]
uhci0: [ITHREAD]
usb0: <VIA 83C572 USB controller> on uhci0
usb0: USB revision 1.0
uhub0: <VIA UHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb0
uhub0: 2 ports with 2 removable, self powered
uhci1: <VIA 83C572 USB controller> port 0xdc00-0xdc1f irq 21 at device 16.1 on p ci0
uhci1: [GIANT-LOCKED]
uhci1: [ITHREAD]
usb1: <VIA 83C572 USB controller> on uhci1
usb1: USB revision 1.0
uhub1: <VIA UHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb1
uhub1: 2 ports with 2 removable, self powered
uhci2: <VIA 83C572 USB controller> port 0xe000-0xe01f irq 21 at device 16.2 on p ci0
uhci2: [GIANT-LOCKED]
uhci2: [ITHREAD]
usb2: <VIA 83C572 USB controller> on uhci2
usb2: USB revision 1.0
uhub2: <VIA UHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb2
uhub2: 2 ports with 2 removable, self powered
ehci0: <VIA VT6202 USB 2.0 controller> mem 0xea02a000-0xea02a0ff irq 21 at devic e 16.3 on pci0
ehci0: [GIANT-LOCKED]
ehci0: [ITHREAD]
usb3: EHCI version 1.0
usb3: companion controllers, 2 ports each: usb0 usb1 usb2
usb3: <VIA VT6202 USB 2.0 controller> on ehci0
usb3: USB revision 2.0
uhub3: <VIA EHCI root hub, class 9/0, rev 2.00/1.00, addr 1> on usb3
uhub3: 6 ports with 6 removable, self powered
isab0: <PCI-ISA bridge> at device 17.0 on pci0
isa0: <ISA bus> on isab0
atapci0: <VIA 8235 UDMA133 controller> port 0x1f0-0x1f7,0x3f6,0x170-0x177,0x376, 0xe400-0xe40f at device 17.1 on pci0
ata0: <ATA channel 0> on atapci0
ata0: [ITHREAD]
ata1: <ATA channel 1> on atapci0
ata1: [ITHREAD]
pci0: <multimedia, audio> at device 17.5 (no driver attached)
acpi_tz0: <Thermal Zone> on acpi0
fdc0: <floppy drive controller> port 0x3f2-0x3f5,0x3f7 irq 6 drq 2 on acpi0
fdc0: [FILTER]
sio0: <16550A-compatible COM port> port 0x3f8-0x3ff irq 4 flags 0x10 on acpi0
sio0: type 16550A
sio0: [FILTER]
sio1: <16550A-compatible COM port> port 0x2f8-0x2ff irq 3 on acpi0
sio1: type 16550A
sio1: [FILTER]
atkbdc0: <Keyboard controller (i8042)> port 0x60,0x64 irq 1 on acpi0
atkbd0: <AT Keyboard> irq 1 on atkbdc0
kbd0 at atkbd0
atkbd0: [GIANT-LOCKED]
atkbd0: [ITHREAD]
pmtimer0 on isa0
orm0: <ISA Option ROM> at iomem 0xd0000-0xd1fff pnpid ORM0000 on isa0
ppc0: <Parallel port> at port 0x378-0x37f irq 7 on isa0
ppc0: SMC-like chipset (ECP/EPP/PS2/NIBBLE) in COMPATIBLE mode
ppc0: FIFO with 16/16/9 bytes threshold
ppbus0: <Parallel port bus> on ppc0
ppbus0: [ITHREAD]
plip0: <PLIP network interface> on ppbus0
lpt0: <Printer> on ppbus0
lpt0: Interrupt-driven port
ppi0: <Parallel I/O> on ppbus0
ppc0: [GIANT-LOCKED]
ppc0: [ITHREAD]
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x300>
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
Timecounter "TSC" frequency 1833918710 Hz quality 800
Timecounters tick every 1.000 msec
hptrr: no controller detected.
ad0: 58644MB <IBM DTLA-307060 TX8FA5AA> at ata0-master UDMA100
acd0: DVDROM <Pioneer DVD-ROM ATAPIModel DVD-113 0116/E1.16> at ata1-master UDMA 33
acd1: DVDR <ASUS DRW-1608P3S/1.06> at ata1-slave UDMA66
Trying to mount root from ufs:/dev/ad0s1a
Zapata Telephony Interface Registered on major 196
Echo Canceller: MG2 (aggressive)
sdla0: <Sangoma AFT-A101d T1/E1 adapter> mem 0xea020000-0xea027fff irq 22 at dev ice 12.0 on pci0
sdla0: [GIANT-LOCKED]
sdla0: [ITHREAD]
wag1: using obsoleted if_watchdog interface
[root@ill /usr/home/macman]#
atkbd0: <AT Keyboard> irq 1 on atkbdc0
kbd0 at atkbd0
atkbd0: [GIANT-LOCKED]
atkbd0: [ITHREAD]
pmtimer0 on isa0
orm0: <ISA Option ROM> at iomem 0xd0000-0xd1fff pnpid ORM0000 on isa0
ppc0: <Parallel port> at port 0x378-0x37f irq 7 on isa0
ppc0: SMC-like chipset (ECP/EPP/PS2/NIBBLE) in COMPATIBLE mode
ppc0: FIFO with 16/16/9 bytes threshold
ppbus0: <Parallel port bus> on ppc0
ppbus0: [ITHREAD]
plip0: <PLIP network interface> on ppbus0
lpt0: <Printer> on ppbus0
lpt0: Interrupt-driven port
ppi0: <Parallel I/O> on ppbus0
ppc0: [GIANT-LOCKED]
ppc0: [ITHREAD]
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x300>
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
Timecounter "TSC" frequency 1833918710 Hz quality 800
Timecounters tick every 1.000 msec
hptrr: no controller detected.
ad0: 58644MB <IBM DTLA-307060 TX8FA5AA> at ata0-master UDMA100
acd0: DVDROM <Pioneer DVD-ROM ATAPIModel DVD-113 0116/E1.16> at ata1-master UDMA33
acd1: DVDR <ASUS DRW-1608P3S/1.06> at ata1-slave UDMA66
Trying to mount root from ufs:/dev/ad0s1a
Zapata Telephony Interface Registered on major 196
Echo Canceller: MG2 (aggressive)
sdla0: <Sangoma AFT-A101d T1/E1 adapter> mem 0xea020000-0xea027fff irq 22 at device 12.0 on pci0
sdla0: [GIANT-LOCKED]
sdla0: [ITHREAD]
wag1: using obsoleted if_watchdog interface

сейчас зупустим тот, что похуже, я с него тоже сниму

вот со второго - который похуже

FreeBSD 7.0-RELEASE (ASTER) #0: Thu Aug 7 11:39:18 EEST 2008
[macman@ill-tmp ~]$ sudo -s
Password:
[root@ill-tmp /usr/home/macman]# cat /var/run/dmesg.boot
Copyright (c) 1992-2008 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
The Regents of the University of California. All rights reserved.
FreeBSD is a registered trademark of The FreeBSD Foundation.
FreeBSD 7.0-RELEASE #0: Thu Aug 7 11:39:18 EEST 2008
root@asterisk-tmp.niko.local:/usr/obj/usr/src/sys/ASTER
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: Intel(R) Xeon(R) CPU 3040 @ 1.86GHz (1866.74-MHz 686-class CPU)
Origin = "GenuineIntel" Id = 0x6f2 Stepping = 2
Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
Features2=0xe3bd<SSE3,RSVD2,MON,DS_CPL,VMX,EST,TM2,SSSE3,CX16,xTPR,PDCM>
AMD Features=0x20100000<NX,LM>
AMD Features2=0x1<LAHF>
Cores per package: 2
real memory = 2145845248 (2046 MB)
avail memory = 2090311680 (1993 MB)
ACPI APIC Table: <PTLTD APIC >
FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs
cpu0 (BSP): APIC ID: 0
cpu1 (AP): APIC ID: 1
ioapic0 <Version 2.0> irqs 0-23 on motherboard
kbd1 at kbdmux0
ath_hal: 0.9.20.3 (AR5210, AR5211, AR5212, RF5111, RF5112, RF2413, RF5413)
hptrr: HPT RocketRAID controller driver v1.1 (Aug 7 2008 11:38:51)
acpi0: <PTLTD XSDT> on motherboard
acpi0: [ITHREAD]
acpi0: Power Button (fixed)
Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000
acpi_timer0: <24-bit timer at 3.579545MHz> port 0x1008-0x100b on acpi0
cpu0: <ACPI CPU> on acpi0
est0: <Enhanced SpeedStep Frequency Control> on cpu0
est: CPU supports Enhanced Speedstep, but is not recognized.
est: cpu_vendor GenuineIntel, msr 728072806000728
device_attach: est0 attach returned 6
p4tcc0: <CPU Frequency Thermal Control> on cpu0
cpu1: <ACPI CPU> on acpi0
est1: <Enhanced SpeedStep Frequency Control> on cpu1
est: CPU supports Enhanced Speedstep, but is not recognized.
est: cpu_vendor GenuineIntel, msr 728072806000728
device_attach: est1 attach returned 6
p4tcc1: <CPU Frequency Thermal Control> on cpu1
pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
pci0: <ACPI PCI bus> on pcib0
pcib1: <ACPI PCI-PCI bridge> irq 16 at device 1.0 on pci0
pci1: <ACPI PCI bus> on pcib1
pcib2: <ACPI PCI-PCI bridge> at device 0.0 on pci1
pci2: <ACPI PCI bus> on pcib2
pci2: <network> at device 3.0 (no driver attached)
pcib3: <ACPI PCI-PCI bridge> irq 16 at device 3.0 on pci0
pci3: <ACPI PCI bus> on pcib3
pcib4: <ACPI PCI-PCI bridge> irq 20 at device 28.0 on pci0
pci4: <ACPI PCI bus> on pcib4
pcib5: <ACPI PCI-PCI bridge> irq 20 at device 28.4 on pci0
pci5: <ACPI PCI bus> on pcib5
em0: <Intel(R) PRO/1000 Network Connection Version - 6.7.3> port 0x4000-0x401f mem 0xd8080000-0xd809ffff,0xd8000000-0xd807ffff irq 16 at device 0.0 on pci5
em0: Using MSI interrupt
em0: Ethernet address: 00:e0:81:4b:a0:be
em0: [FILTER]
pcib6: <ACPI PCI-PCI bridge> irq 21 at device 28.5 on pci0
pci6: <ACPI PCI bus> on pcib6
em1: <Intel(R) PRO/1000 Network Connection Version - 6.7.3> port 0x5000-0x501f mem 0xd8280000-0xd829ffff,0xd8200000-0xd827ffff irq 17 at device 0.0 on pci6
em1: Using MSI interrupt
em1: Ethernet address: 00:e0:81:4b:a0:bf
em1: [FILTER]
uhci0: <UHCI (generic) USB controller> port 0x3000-0x301f irq 23 at device 29.0 on pci0
uhci0: [GIANT-LOCKED]
uhci0: [ITHREAD]
usb0: <UHCI (generic) USB controller> on uhci0
usb0: USB revision 1.0
uhub0: <Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1> on usb0
uhub0: 2 ports with 2 removable, self powered
ehci0: <Intel 82801GB/R (ICH7) USB 2.0 controller> mem 0xd8600000-0xd86003ff irq 23 at device 29.7 on pci0
ehci0: [GIANT-LOCKED]
ehci0: [ITHREAD]
usb1: waiting for BIOS to give up control
usb1: timed out waiting for BIOS
usb1: EHCI version 1.0
usb1: companion controller, 2 ports each: usb0
usb1: <Intel 82801GB/R (ICH7) USB 2.0 controller> on ehci0
usb1: USB revision 2.0
uhub1: <Intel EHCI root hub, class 9/0, rev 2.00/1.00, addr 1> on usb1
uhub1: 2 ports with 2 removable, self powered
pcib7: <ACPI PCI-PCI bridge> at device 30.0 on pci0
pci10: <ACPI PCI bus> on pcib7
vgapci0: <VGA-compatible display> port 0x6000-0x60ff mem 0xd0000000-0xd7ffffff,0xd8300000-0xd830ffff irq 19 at device 2.0 on pci10
isab0: <PCI-ISA bridge> at device 31.0 on pci0
isa0: <ISA bus> on isab0
atapci0: <Intel ICH7 SATA300 controller> port 0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,0x3050-0x305f at device 31.2 on pci0
ata0: <ATA channel 0> on atapci0
ata0: [ITHREAD]
ata1: <ATA channel 1> on atapci0
ata1: [ITHREAD]
pci0: <serial bus, SMBus> at device 31.3 (no driver attached)
acpi_button0: <Power Button> on acpi0
atkbdc0: <Keyboard controller (i8042)> port 0x60,0x64 irq 1 on acpi0
atkbd0: <AT Keyboard> irq 1 on atkbdc0
kbd0 at atkbd0
atkbd0: [GIANT-LOCKED]
atkbd0: [ITHREAD]
pmtimer0 on isa0
orm0: <ISA Option ROM> at iomem 0xc0000-0xc8fff pnpid ORM0000 on isa0
ppc0: parallel port not found.
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x300>
sio0: configured irq 4 not in bitmap of probed irqs 0
sio0: port may not be enabled
sio0: configured irq 4 not in bitmap of probed irqs 0
sio0: port may not be enabled
sio0 at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0
sio0: type 8250 or not responding
sio0: [FILTER]
sio1: configured irq 3 not in bitmap of probed irqs 0
sio1: port may not be enabled
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
Timecounters tick every 1.000 msec
hptrr: no controller detected.
ad3: 238475MB <Seagate ST3250820NS 3.AEK> at ata1-slave SATA150
SMP: AP CPU #1 Launched!
Trying to mount root from ufs:/dev/ad3s1a
WARNING: / was not properly dismounted
WARNING: /var was not properly dismounted
WARNING: /usr was not properly dismounted
Zapata Telephony Interface Registered on major 196
Echo Canceller: MG2 (aggressive)
sdla0: <Sangoma AFT-A101d T1/E1 adapter> mem 0xd8100000-0xd8107fff irq 17 at device 3.0 on pci2
sdla0: [GIANT-LOCKED]
sdla0: [ITHREAD]
wag1: using obsoleted if_watchdog interface
Registered tone zone 0 (United States / North America)

Извиняюсь, что в Вашу тему залез, но не хотел плодить похожие.
Моя ситуация:

Opened pseudo zap interface, measuring accuracy...
99.987793% 99.987793% 99.975586% 99.987793% 99.975586% 99.987793% 99.987793%
99.975586% 99.987793% 99.987793% 99.987793% 99.987793% 99.987793% 99.975586%
--- Results after 14 passes ---
Best: 99.987793 -- Worst: 99.975586 -- Average: 99.984305

100% вообще никогда не видел ... Правда факсы вроде ходят, сильно много страничные не пробовал.

Карточка Tor2B2.

cat /proc/interrupts:
CPU0 CPU1 CPU2 CPU3
0: 100887227 100950450 100885120 100953433 IO-APIC-edge timer
1: 47 37 45 39 IO-APIC-edge i8042
8: 0 1 0 1 IO-APIC-edge rtc
9: 0 0 0 0 IO-APIC-fasteoi acpi
14: 10 9 8 10 IO-APIC-edge ide0
16: 8451486 8381606 8442222 8394220 IO-APIC-fasteoi aacraid, eth0
18: 357117 362664 356315 362164 IO-APIC-fasteoi eth1
20: 336380278 336381212 336392269 336366112 IO-APIC-fasteoi tor2
NMI: 0 0 0 0
LOC: 403674202 403674201 403674200 403674199
ERR: 0
MIS: 0

uname -a:

Linux pbx.astra.od.ua 2.6.20-gentoo-r8 #4 SMP Tue Aug 26 17:34:07 EEST 2008 i686 Intel(R) Xeon(R) CPU 5130 @ 2.00GHz GenuineIntel GNU/Linux

lsmod:

Module Size Used by
tun 9280 1
usbcore 91988 0
snd_pcm_oss 36000 0
snd_mixer_oss 14720 1 snd_pcm_oss
snd_pcm 62020 1 snd_pcm_oss
snd_timer 18052 1 snd_pcm
snd_page_alloc 8904 1 snd_pcm
snd 40484 4 snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_timer
tor2 86496 0
zaptel 174524 67 tor2
crc_ccitt 3776 1 zaptel
ata_generic 6916 0

zaptel-1.2.16

HZ=1000

Есть ли методы поднять measuring accuracy ?

у меня было строго 100%, когда включал астер в астер по Е1. на слейве было жёстко 100%
в "СТЕМ"-е мне тоже показывали диджиумовскую карточку на сусе - тоже было 100%

у меня сейчас на "хорошей" материнке так:
--- Results after 64 passes ---
Best: 100.000000 -- Worst: 99.987793 -- Average: 99.992943


какие Вы АТА-шки используете?