is it possible the book was accurate at the time of writing but hardware has since improved? -pete
-- (peter.royal|osi)@pobox.com - http://fotap.org/~osi > On Jul 1, 2022, at 8:54 PM, Peter Veentjer <alarmnum...@gmail.com> wrote: > > > Hi, > > I'm reading the following book "Developing High-Frequency Trading Systems". > My goal is not to write any high-frequency trading systems, but to get some > insights into the domain and learn as much as possible from the applied > techniques. It is a Packt book and they are not known for their quality. But > it is written by 3 engineers with a combined HFT experience of almost 50 > years. > > On page 62 of the book, they make the following claim. If you are using a > hyper-threading and there is an interrupt or a system call on one logical > core, then the hyper-sibling will stall as well because both need access to > the kernel (mode switch). > > I don't believe this is correct. Each logical core has its own architectural > state; so its own set of architectural registers and its own APIC including > an interrupt descriptor table. The current privilege level is stored in the > first 2 bits of the CS register and since every logical core has its own copy > of that, the hyper siblings should be able to run independently no matter if > there is a mode switch. > > Of course, disabling hyper-threading will lead to improved performance of a > single core, because it doesn't need to share any resources like rob, line > fill buffers, store buffers, load buffets, execution units, reservation > stations, caches, etc. So that is a valid reason to disable hyper-threading. > > I'm by no means an X86 expert and certainly not a high-frequency trading > expert. So perhaps I'm missing something. > > Regards, > > Peter. > > > -- > You received this message because you are subscribed to the Google Groups > "mechanical-sympathy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to mechanical-sympathy+unsubscr...@googlegroups.com. > To view this discussion on the web, visit > https://groups.google.com/d/msgid/mechanical-sympathy/CAGuAWdChA2kzo1RXHUB3Zh1H5GonVs82BhkCzG7ap4Q1PaUvdg%40mail.gmail.com. -- You received this message because you are subscribed to the Google Groups "mechanical-sympathy" group. To unsubscribe from this group and stop receiving emails from it, send an email to mechanical-sympathy+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/mechanical-sympathy/473A9790-D9B6-46DA-8C8C-8FD98957EB76%40pobox.com.
