Zttest on Dell PowerEdge with TDM 410P

I am running asterisk 1.4.19 on Dell poweredge running CentOS 5 with TDM 410P

zttest is reporting 100.093% occassionally!

lspci -vb shows that IRQ 5 is shared between ethernet controllers and the Digium card.

lspci -v shows the following indicating that the tdm card has unique virtual IRQ

90: 101618597 0 IO-APIC-level wctdm24xxp0
98: 66940 0 PCI-MSI eth0
106: 1916584 0 PCI-MSI eth1

My question is why zttest is showing value greater that 100% and then immediately drops to 99.89% . Will I have trouble if I put this box in production? Any help will really be appreciated.

8192 zaptel samples in 8191.607 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.600 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.592 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.632 system clock sample intervals (99.996%)
8192 zaptel samples in 8191.616 system clock sample intervals (99.995%)
8192 zaptel samples in 8199.600 system clock sample intervals (100.093%)
8192 zaptel samples in 8183.576 system clock sample intervals (99.897%)
8192 zaptel samples in 8191.600 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.616 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.600 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.600 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.568 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.631 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.575 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.584 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.543 system clock sample intervals (99.994%)
8192 zaptel samples in 8191.600 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.616 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.608 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.607 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.600 system clock sample intervals (99.995%)
8192 zaptel samples in 8191.600 system clock sample intervals (99.995%)
8192 zaptel samples in 8199.672 system clock sample intervals (100.094%)
8192 zaptel samples in 8183.528 system clock sample intervals (99.897%)
8192 zaptel samples in 8191.616 system clock sample intervals (99.995%)
8192 zaptel samples in 8199.655 system clock sample intervals (100.093%)
8192 zaptel samples in 8183.417 system clock sample intervals (99.895%)
8192 zaptel samples in 8191.495 system clock sample intervals (99.994%)

I booted with noapic . It’s performing much better now. Following is the result I get.

— Results after 489 passes —
Best: 99.997 – Worst: 99.992 – Average: 99.994926, Difference: 99.994926

I am still concerned that the ethernet controllers and TDM card have the same IRQ of 5 when I do lspci -vb

Any comments? Is it alright since zttest is showing good results? Will I have trouble if the network load is high?