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I have a Threadripper 3970x that has 32 cores and 64 threads. I installed Linux and the kernel shows SMT as being "notsupported": root@services:~# cat /sys/devices/system/cpu/smt/control ...
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I have a computation intensive process that I need to run multiple times on a multi-core processor but "top" isn't showing utilization or load in a useful way. For example, imagine my task ...
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I am using whisper.cpp to transcribe some sound files. It is a very CPU heavy process so I try to find some optimal settings and therefore I have done some tests with the thread setting (-t) but the ...
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Per the title, I have a Supermicro X10-DRLi based machine with 2x E5-2666 V3 (the Amazon OEM CPUs) in it. Secure Boot, FWIW, is disabled. Linux 5.10 (debian 11 stock kernel, amd64) tells me via the /...
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Suppose I have an 18 core CPU with SMT enabled, and there are 18 long runnning processes, all using ~100% of a thread. If I start a 19th process, the kernel will schedule it to run on one of the cores,...
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I'm trying to confirm that my AMD EPYC 7601 CPUs are set up with dual threading. I have 2 X 32 CPUs and ​should have 2 threads per CPU. When I run: lscpu | grep -E '^Thread|^Core|^Socket|^CPU\(' I ...
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I have a Ryzen 3 3200g and, when I do lscpu in a Linux Mint 20.1 Cinnamon OS terminal, the output says that I only have 1 thread per core. The Windows system's info accurately recognizes that my CPU ...
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Because of hyper-threading, my CPU has 2 logical processors per core. If I understand the premise of hyper-threading correctly, it allows each core to have a separate cache and instruction pointer for ...
Charlim's user avatar
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In Solaris, how we can find the status or check hyper-threading or multi-threading is enabled or not using commands?
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We are creating virtual os threads inside guest os but the actual physical core is on the host machine. Will hyperthread = true in guest VM config make any difference? I can visualize how ...
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The following is what I am doing to tell whether a processor does support HT or not, regardless of whether it is enabled or disabled: # dmidecode -t processor | grep "Hardware Thread" | wc -l If ...
Raulinbonn's user avatar
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I would like to know if hyperthread can be enabled on my operating system or not? I am using HP-UX Itanium, below is truncated output of machinfo Intel(R) Itanium(R) Processor 9560 (2.53 GHz, 32 ...
Learning_DBAdmin's user avatar
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I have some i7-4700EQ based embedded server systems that require hyperthreading. All is good except that, on rare occasions, the hyperthreading flag in CMOS gets set to disabled. While the hardware ...
Hugh McCurdy's user avatar
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Are there any methods (linux kernel options, sysctl settings or configurable scheduler modules) that can cause a high priority process/thread to run on a physical processor core with the second (hyper ...
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I know it should be a simple matter of grep -wl ht /proc/cpuinfo but that's not always accurate. I have an i5-7440HQ CPU which doesn't support hyper-threading (Intel, WikiPedia, and my BIOS agree on ...
TheAmigo's user avatar
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VirtualBox: As I have Hyper-Threading capable CPU, I wonder: Is it a bad idea to assign more virtual CPU cores than a number of physical CPU cores as the following warning suggests (simply using all 8 ...
Vlastimil Burián's user avatar
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Are there UNIX variants or other OS which make user level threads visible to OS kernel ?
bawejakunal's user avatar
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I'm running iperf in server mode on a Ubuntu box (14.04 LTS). The hardware is quad core with hyper-threading, so I have cores 0-7 available (0 is paired with 4, 1 with 5 and so on). I've set the ...
Andrew Parker's user avatar
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The CPU is a [email protected]. It has 4 cores and each core has 2 threads. Here is the dmidecode output: # dmidecode -t 4 # dmidecode 2.9 SMBIOS 2.7 present. Handle 0x0042, DMI type 4, 42 bytes ...
Chris Tsui's user avatar
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If I have two physical cores and hyperthreading enabled, is the CPU load computed against two cores or fours? In other words, is complete load indicated by 2.0 or 4.0?
rubik's user avatar
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We've currently bought a new server, with 64 GB of RAM and 8 cores with hyperthreading support. We are going to build a system using: nginx. apache. mysql. php So, the question is about performance: ...
SPIRiT_1984's user avatar
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I wanted to determine if a machine has hyperthreading enabled or not. To determine this, I used advice I found online, which operates as follows: physical_proc_count = `grep "physical id" /proc/...
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I'm running Oracle 10 on a blade450 g6. I have hyper-threading turned on but I have heard several people say that Oracle databases don't play well with it. Are there specific performance or ...
Joe's user avatar
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I have a Dell server with two Intel Xeon E5645 cpus, each cpu has 6 cores, and each core is hyperthreaded (i.e. should be equivalent to two virtual cores). I installed CentOS 6.2 on this server and it ...
Oren Mel's user avatar
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3 votes
1 answer
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When I enable hyperthreading, CPU size and capacity decrease to about half the non-hyperthreaded value. Since most of my processes use only two cores, should I disable hyperthreading? lshw -C ...
Raphael Calmon's user avatar
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How can I check if hyperthreading is enabled on a Linux machine, using a perl script to check for it? I'm trying the following way: dmidecode -t processor | grep HTT Let me know if I'm on right ...
doubledecker's user avatar
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I use a i5-2410M processor, which is setup to do hyperthreading by default on my laptop. Considering that this is a 2-core processor, this means it can do 4 threads at a time. This also means that ...
tshepang's user avatar
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Is it possible to find out if hyperthreading is enabled within the BSD kernel of a given machine without watching the boot up sequence?
Mark D's user avatar
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3 answers
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I understand that Σ(%CPU) ≤ logicalcores*(1+ε) (where ε is measure and rounding error). But, how can I have on a 2 core system 2 different processes, each taking 200% of CPU (as measured by htop)? ...
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