From: Isaac Boukris <iboukris@gmail.com>
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: users@dpdk.org
Subject: Re: Accuracy of rte_get_tsc_hz() compared to linux
Date: Thu, 19 Sep 2024 16:04:34 +0300 [thread overview]
Message-ID: <CAC-fF8T_T1W2zsWH3J8VQiRJDfh3LWNx8z6825U8ed5rNbBCoQ@mail.gmail.com> (raw)
In-Reply-To: <CAC-fF8R+4byOq3iuoZ8oxuedQZjr3XwSibruvzmy5KNOJzP+Sw@mail.gmail.com>
On an older laptop (i7-8650U), running fedora with kernel 6.8.9-100.fc38.x86_64
journalctl -b | grep -i tsc
Aug 29 12:34:00 localhost.localdomain kernel: tsc: Detected 2100.000
MHz processor
Aug 29 12:34:00 localhost.localdomain kernel: tsc: Detected 2099.944 MHz TSC
Aug 29 12:34:00 localhost.localdomain kernel: TSC deadline timer available
Aug 29 12:34:00 localhost.localdomain kernel: clocksource: tsc-early:
mask: 0xffffffffffffffff max_cycles: 0x1e44fb6c2ab, max_idle_ns:
440795206594 ns
Aug 29 12:34:00 localhost.localdomain kernel: clocksource: Switched to
clocksource tsc-early
Aug 29 12:34:00 localhost.localdomain kernel: tsc: Refined TSC
clocksource calibration: 2112.000 MHz
sudo bpftrace -e 'BEGIN { printf("%u\n", *kaddr("tsc_khz")); exit(); }'
Attaching 1 probe...
2112000
dpdk logs before lowering the rounding:
EAL: TSC frequency arch ~0 KHz
EAL: TSC frequency linux ~2110000 KHz
EAL: TSC frequency estimate ~2110000 KHz
after lowering the rounding to 1KHz:
EAL: TSC frequency arch ~0 KHz
EAL: TSC frequency linux ~2112000 KHz
EAL: TSC frequency estimate ~2112949 KHz
next prev parent reply other threads:[~2024-09-19 13:04 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-09-18 22:04 Isaac Boukris
2024-09-18 23:27 ` Stephen Hemminger
2024-09-19 9:37 ` Isaac Boukris
2024-09-19 12:26 ` Isaac Boukris
2024-09-19 13:04 ` Isaac Boukris [this message]
2024-09-19 18:33 ` Isaac Boukris
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