Rages disk-less Windows 10 boot from iscsi - Adventures / Results

so, rechecked dateset and zvol configuration and Atime was still on, on the dataset. Disabled the sync option and tried again.
The boot times didn’t change at all with that. i’m still at 1min 40sec off of the ssds.

And i forgot to take a snapshot and installed a beta driver and killed it.
Windows Recovery is not able to boot right now. The LWF caused Inaccassable_boot_device. So i can’t even get into safe mode any more. Yay.

Not in the office today, but i’ll hopefully be able to get you the details of my work setup tomorrow.

OK fedora /etc/fstab

10.42.2.20:/mnt/ZFS-POOL-1/jr-nfs /home/jethror/nfs nfs user

this mounts my “jr-nfs” share under /home/jethror/nfs as a user

on the freenas side:

Resulting in:
[jethror@aud7120gmn ~]$ df
Filesystem 1K-blocks Used Available Use% Mounted on
10.42.2.20:/mnt/ZFS-POOL-1/jr-nfs 3.6T 27G 3.5T 1% /home/jethror/nfs

IP address of my Freenas box is 10.42.2.20 (obviously?).

“jethror” is a local account on both the FreeNAS workstation and the ZFS server (i.e., 2 seperate accounts, i log into both machines using local to each machine account jethror - no central auth).

The jr-nfs dataset has security permissions for this user on the ZFS end, and the above mapall user ensures that whatever credentials are used to connect to the NFS export, the local ZFS user permisisons for reading/writing the share will be the local FreeNAS jethror account.

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Did a Windows Upgrade, 1809 to the next higher one and it killed the binding blacklist and caused an the known bsod. Well Done M$.

And plain iscsi is single-Thread limited by my NAS CPU.

i can now for certain say that windows, freenas and iPXE currently only support iscsi, that is without RDMA and it is therefore single thread limited on the server / target side.
In my case, a Xeon e5 2628L v4 which fucking sucks at single thread.
Hence the abysmal performance!

Seems like an evil scheme from Intel to push their old high frequency 14 nm parts :wink:

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Sorry for switching between threads, I think this is more suitable here.

Might I suggest that your FreeNAS CPU is not the problem for the abysmal performance?

I did a little research and booting should not be that slow.

Debian seems to boot in under 30 seconds, possibly under 20 on this video: https://youtu.be/z_P79jvJV-E?t=1310

That FreeNAS machine is running an Opteron 6172. Can’t imagine that is faster than your Xeon. Also, CPU usage during iSCSI operations suggest the use of more than one core. 20% - 30% usage of 12 cores.

I also asked this on the ixsystems forum and got this reply:

I suggest adding a second DIMM, relocating the NIC to a slot with direct access to the CPU and trying a different NIC, even an onboard one if it supports network booting. Also, how full are the SSDs?

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Ok. In retrospect, putting the Nic on a PCH By4 Lane might be part of the performance problem.

It isn’t from the throughput side for that Sata ssd, but could be in terms of latency.

To answer your particular question from that ix thread.
Yes, you can do that kind of thing with Freenas.
Though i haven’t figured out how to do that fully automatic.
Zfs has so called Zvols that can be snapshot-ed and a snapshot can be cloned. A Clone is a exact copy that snapshot-ed thing, but doesn’t waste any space and is based on the snapshot-ed data. Once you change something in the clone, only the differences take up space.
Copy On Write in its core.

And yes, the L Xeon isn’t necessarily that great of a CPU for that job.

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Have you ever thought latency might be your problem? Whoever suggested NVME probably had a point, its not just the actual speed thats important, the latency can have a huge difference to any os running over the network.

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not really, but possible.
I didn’t realize then that it’s on a PCH Slot, and i don’t think i ran iperf tests so i was stupid in hindsight.
Though, it has beenmore then two years, and i have not fiddled with it since then.
Didn’t deploy it either because it was utterly unusable for a OC Testbench with constantly changing hardware and upgrades killed it aswell.
Thx windows Lightweight Filter driver.

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