Hi, I've been investigating networking performance for Windows 2003 guests on a Solaris dom0 and I've uncovered a couple of things which I don't really understand and I'm looking for some explanations. This first question is really directed at virtinst developers... Windows guests have different ACPI and APIC settings depending on which variant of Windows is to be installed: variant: unspecified -> ACPI: true, APIC: true variant: winxp -> ACPI: false, APIC: false variant: win2k -> ACPI: false, APIC: false variant: win2k3 -> ACPI: true, APIC: true variant: vista -> ACPI: true, APIC: true The question is: why don't all Windows variants have the same ACPI and APIC settings? The reason I'm curious, is that it seems like different combinations of APIC and ACPI produce different functionality in the guest and different levels of performance. I did some tests with win2k3 guests and measured networking performance using iperf. I used the same dom0 system (snv_103) and created three W2K3 guests, each with 1 CPU but different APIC and ACPI settings: apic/acpi setting results (Mb/s throughput) apic: 0 acpi: 0 834, 833 apic: 1 acpi: 1 718, 704 apic: 0 acpi: 1 872, 876 (higher numbers are better) I only had time to perform two runs (the test is the iperf-2.0.2 1MB msg test that I ran to microbenchmark TCP performance) for each guest, but you can see that there is a fairly large and consistent (across two runs for each guest) performance difference. It's about 20% faster when apic is not specified for the guest. My next question is: What is really happening when APIC is specified for a windows guest and why does performance vary so much according to whether it's specified or not? Thanks for any help or insight anyone can offer. Gary -- Gary Pennington Solaris Core OS Sun Microsystems Gary.Pennington@xxxxxxx _______________________________________________ et-mgmt-tools mailing list et-mgmt-tools@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/et-mgmt-tools
