Dear gentlemen, I've been following your debate, and while it's a sin to comment off topic, it's difficult for me to hold back the following smirk:
i82579V/LM brings back a recollection of a pretty famous bug discovered a few years ago, where PCI-e ASPM did not work properly, with the net result originally described as "low double digit per cent" of packet loss. Possibly originally reported for this particular chip... maybe because it was so ubiquitous: the i82579 is the external PHY chip of the LOM MAC integrated in the 6-series Intel south bridges (companion to SandyBridge CPU's). But actually the ASPM bug used to plague several Intel gigabit adaptor models of that era. I can't seem to find the bugzilla entry or mailing list thread... but I'm pretty sure someone close to the Linux kernel development finally nailed the bug after several months of its first report, and patched it in the kernel by disabling ASPM in the Intel NIC driver. Not sure which one it was, e1000e or igb or what, and what kernel version. A month or so later, this also got "fixed" in the Windows driver by Intel. I surely agree that a problem waking up the PCI-e lane from shallow sleep doesn't sound like something that would freeze the on-chip PHC for a fixed time quantum every time it gets asked :-) especially if the workaround is just to disable ASPM altogether. While googling in vain for traces of that bug, I've found a *different* bug report related to the i82579: https://bugzilla.redhat.com/show_bug.cgi?id=713315 Again... I'm not saying that this is necessarily related. Just that the 82579 probably had its share of issues ;-) that possibly got worked around in drivers. So it seems that I superficially agree with Mr. Keller on that one... (P.S.: not mentioning the "occasional cfg EEPROM invalidation issue", which seems totally unrelated and generic across the Intel NIC product line.) Don't get me wrong - I'm a great fan of Intel x86 silicon, including the accompanying chipsets and peripheral stuff. Feels like home to me. Bugs get fixed. I've seen worse elsewhere. Frank Rysanek _______________________________________________ Linuxptp-devel mailing list Linuxptp-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-devel
