Playing with fq_codel in 2.4
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I have stopped playing for now and moved back to HFSC ingress and fairq egress.
Suddenly thats improved due to the changes I made to try and help dummynet.
I did some tuning based on the information here (the author of isr code)
http://alter.org.ua/soft/fbsd/netisr/
I disabled interrupt moderation on my 2 intel ports.
I increased kernel timer rate which doesnt help interrupt overheads but I have the spare cpu clocks idle.
Now ALTQ+ HFSC is handing steam no problem at 97%, the latency performance is much closer to fq_codel as well.
I dont know yet if my iptv issues will improve or if I will still need to temporarily disable ingress ALTQ when relying on the iptv stuff.
The netisr changes I consider experimental of course as it goes against what I considered good practice (and obviously what pfsense considers good practice) the author seems to suggest deffere mode for netisr is superior for routing and direct is only best when running as a server, especially the case when you have more cpu cores than network cards.
Hopefully more people will contribute to this thread on their experience of dummynet fq_codel vs ALTQ shaping (particurly HFSC).
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Increased the timer rate? It defaulted to 1000hz for me or at least I don't remember changing it. Was it lower for you or did you increase it even more? FreeBSD 10 added tickless kernel scheduling. I'm not sure kern.hz even applies anymore.
I'm also getting good results from ALTQ+HFSC+Codel
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yeah by default it runs double the kern hz on my unit, I had set it back to legacy behaviour so 1000khz timer, but for this I removed my override so its 2000 per second on each core.
By the way I think now this is a PPS issue that my unit is failing to handle when its too high.
It seems HFSC drops the PPS quite aggressively when it is in play and this is why it is working better for me, from what I can tell my unit starts dropping random packets when PPS is over about 1500 when it reaches 2500 or so it gets quite bad, although the download is never affected visibly.
I do have NAT, no cpu cores are been saturated, pfsense is behind a vdsl modem I have in bridge mode so there is also a chance that modem is not handling the higher pps itself.
So at least for now I will keep my feedback out of this thread given the problem for me might be related to me hitting a PPS bottleneck.
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Sounds like something is wrong. My i5-3.2ghz Haswell Intel-i350T2 is handling 1.44Mpps with HFSC+Codel just fine. 400Kpps is about 15-20% load and 1.44Mpps is about 20%-25% load. And I still get about 1ms pings while doing this.
I have some forum posts around about what changes I made, like enabling MSI-X (enable soft interrupts if your NIC properly supports it) and removing the limitation on the number of packets to process per interrupt, which is by default 40 I think.
I used to process 1.44Mpps at only 600 interrupts per second, but over the years, it is now about 1,200 interrupts per second. All I know is CPU is low, interrupts are low, latency and jitter and loss are low. Even with only 300 interrupts per core per second.
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agree something is wrong, problem is I dont know what at the moment. :)
Will diagnose some more at some point.
MSIX is enabled by default on my i350, I actually temporarily disabled it already to try and get to bottom of it but MSIX in this case is not the solution. The packets per interrupt is something I not heard off, you know where that is configured?
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agree something is wrong, problem is I dont know what at the moment. :)
Will diagnose some more at some point.
MSIX is enabled by default on my i350, I actually temporarily disabled it already to try and get to bottom of it but MSIX in this case is not the solution. The packets per interrupt is something I not heard off, you know where that is configured?
I guess it's not 40. Not sure what "40" is. I definitely remembering something.
https://calomel.org/freebsd_network_tuning.html
Intel igb(4): FreeBSD puts an upper limit on the the number of received
packets a network card can process to 100 packets per interrupt cycle. This
limit is in place because of inefficiencies in IRQ sharing when the network
card is using the same IRQ as another device. When the Intel network card is
assigned a unique IRQ (dmesg) and MSI-X is enabled through the driver
(hw.igb.enable_msix=1) then interrupt scheduling is significantly more
efficient and the NIC can be allowed to process packets as fast as they are
received. A value of "-1" means unlimited packet processing and sets the same
value to dev.igb.0.rx_processing_limit and dev.igb.1.rx_processing_limit .
hw.igb.rx_process_limit="-1" # (default 100 pps, packets per second)
I want to say that when I echo'd my system settings, msix was disabled and I had to explicitly add it to pfSense to enabled it. I'm also under the impression that many NICs that claim to support MSIX, do not correctly and have odd bugs when msix is enabled, so it was turned off. I'm going off of memory from a long while ago when I was researching.
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yeah mine has definitely been on, checked via dmesg.
I will turn it back on, I only turned off just to check if somehow it was not working properly.
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I've got some great results with fq_codel, it makes significant improvements on wifi where latency can be a real problem!
https://forum.pfsense.org/index.php?topic=135843.msg745944#msg745944
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I think its interrupt related.
I enabled polling on both nic's in use and the packet loss when downloading of steam or meganz is gone.
Before I enabled polling I was observing the interrupts/sec, first the AIM (adaptive interrupt moderation) seems to not be working on my i350 ports as it has no affect, secondly I will generate 8000/sec interrupts for a download of about 70mbit/sec. I see people on here reporting similar usage but for half a gigabit/sec, so it seems two things pointing to moderation not working.
altq reports around 2000 pps, assuming thats accurate then some how I have 4 interrupts for every packet.
I have seen threads on here regarding fake i350's, I dont think its impossible mine is fake which could explain the broken AIM.
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You can get the number off of your nic and run it through Intel.com to see if it's valid.
https://www.intel.com/content/www/us/en/support/network-and-i-o/ethernet-products/000007074.html -
How did you enable polling?
I am not quite sure this is good idea anyway, but I can't see this option in GUI anymore, is it moved somewhere?
You'd better try to add boot.conf.local "safe" settings for Intel cards
hw.igb.num_queues=2
dev.igb.0.fc=0
dev.igb.1.fc=0
Also I have disabled hardware TCP segmentation offload and hardware large receive offload.
P.S. In addition to Harvy66 post
https://forums.servethehome.com/index.php?threads/chinese-intel-i350-adapters.3746/#post-58686 -
I compiled it into the kernel and then enabled it in the cli via ifconfig, I dont think you can enable it with a module.
Polling is seen as pointless now days, but only because modern intel and broadcom hardware do interrupt moderation, for some reason my i350 isnt moderating the interrupts.
I have already disabled flow control and played with the queues, all that made no difference.
When I can be bothered I will check how harvy said, although I am already pretty sure I had no such label on my card.
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Looks like most of those chinese Intel cards are failing because of cheap fake Delta ethernet transformers used on their boards, but it always come up with packet loss and I don't think that AIM could be affected. I think they all using Intel chipset not some fake remarked crap realtek.
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Well I am just speculating.
There is no difference in the interrupts with aim on or off, and the amount of interrupts generated seems high for the pps/bw used. So that suggests to me aim isnt working.
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I have not tested AIM in any way you did it, so I can't say why it's working or not.
Also I've never seen packet loss on my igb cards, some chinese, not fake, but Winayo branded Intel NICs.
https://forums.freebsd.org/threads/62406/#post-360467 I see you are already digging deeper.
Did you already read that https://forums.servethehome.com/index.php?threads/comparison-intel-i350-t4-genuine-vs-fake.6917/ ? We must be 100 percent sure which card you have exactly. May be some photos? -
yep read that thread which is why I made that comment about the fake cards. When I can be bothered I will take closer photos of the card both sides.
I also yes have been considering flashing the firmware, but is not much documentation on how to use bootutil, the only guides I found were when using a uefi shell but they do not explain how to boot into a uefi shell.
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Most of the UEFI motherboards will eat the bootmgr.efi placed in EFI\Microsoft\Boot\bootmgr.efi on FAT32 formatted USB flash.
Here you can find how to obtain it https://wiki.archlinux.org/index.php/Unified_Extensible_Firmware_Interface#Obtaining_UEFI_Shell
I've used binaries from https://github.com/tianocore/edk2/tree/master/ShellBinPkg
From what I've learned reading forums the first sign that this is a fake is the price and redrawn "Delta-like" ethernet transformers on it. -
thanks for the help guys I do appreciate it.
I havent really got alternative kit to test on, but I managed to get pfsense running in esxi, after spending a couple of hours looking for a second nic (dual port server class intel nic I put in there both ports dead) and using vmx drivers in 2.4-RC is fine without polling. So I am putting this down to a dodgy hardware setup and I think I am going to replace my unit.
But I am now going to leave this VM running so I can take the photos and play around with the firmware in the meantime without worrying about downtime.
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I also yes have been considering flashing the firmware, but is not much documentation on how to use bootutil, the only guides I found were when using a uefi shell but they do not explain how to boot into a uefi shell.
I described how to flash via EFI here https://forum.pfsense.org/index.php?topic=112968.msg629211#msg629211
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thanks is flashed, will post pics tomorrow but in a different thread as I am derailing this thread too much. I will edit this post with the link after I posted.
thread here https://forum.pfsense.org/index.php?topic=136561.new#new
