Why MySQL (paid supported version from Oracle) causes hyper threading?
Issue
Oracle MySQL causes hyper threading by using only 1 CPU, which is handling all transactions.
# cat interrupts
CPU0 CPU1 CPU2 CPU3 CPU4 CPU5 CPU6 CPU7
0: 2167854801 0 0 0 0 0 0 0 IO-APIC-edge timer
1: 3 0 0 0 0 0 0 0 IO-APIC-edge i8042
5: 0 0 0 0 0 0 0 0 IO-APIC-level ehci_hcd:usb1, ohci_hcd:usb2, ohci_hcd:usb
8: 1 0 0 0 0 0 0 0 IO-APIC-edge rtc
9: 0 0 0 0 0 0 0 0 IO-APIC-level acpi
12: 5 0 0 0 0 0 0 0 IO-APIC-edge i8042
66: 36 0 0 0 0 0 0 0 IO-APIC-level uhci_hcd:usb4
74: 135198629 0 0 0 0 0 0 0 PCI-MSI cciss0
98: 4262186501 0 0 0 0 0 0 0 PCI-MSI eth0
106: 24247371 0 0 0 0 0 0 0 PCI-MSI eth1
114: 718162701 0 0 0 0 0 0 0 PCI-MSI eth2
122: 25096631 0 0 0 0 0 0 0 PCI-MSI eth3
169: 130604790 0 0 0 0 0 0 0 IO-APIC-level qla2xxx
177: 130697839 0 0 0 0 0 0 0 IO-APIC-level qla2xxx
NMI: 253074 28726 38044 31343 26489 16586 46228 49604
LOC: 2167646381 2167646387 2167646311 2167646230 2167646161 2167646086 2167646011 2167645936
ERR: 0
MIS: 0
Environment
- Red Hat Enterprise Linux 5.7
- MySQL 5.5.17
- HP ProLiant BL465c G5 (2x2 dual core processors)
Subscriber exclusive content
A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.