Ethernet uses a Maximum Transfer Unit (MTU) of 1,500 bytes. This limits the maximum size of an Ethernet packet to 1,500 bytes. Larger I/O requests are split into multiple MTU-sized packets. Transmitting a large number of small packets impacts the host CPU by generating an excessive number of interrupts for each application I/O.
Typical database environments transfer data in 2KB to 32KB sizes which always require multiple 1,500 byte packets per database I/O. Jumbo frames increase the device MTU size to a larger value (typically 9,000 bytes) allowing I/O requests to more frequently fit in one physical packet and reducing the number of frames required for larger I/O requests.
Typical database environments transfer data in 2KB to 32KB sizes which always require multiple 1,500 byte packets per database I/O. Jumbo frames increase the device MTU size to a larger value (typically 9,000 bytes) allowing I/O requests to more frequently fit in one physical packet and reducing the number of frames required for larger I/O requests.
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