Navigation: Linux Kernel Driver DataBase - web LKDDB: Main index - C index

CONFIG_CRYPTO_DEV_QCE_SW_MAX_LEN: Default maximum request size to use software for AES

General informations

The Linux kernel configuration item CONFIG_CRYPTO_DEV_QCE_SW_MAX_LEN:

Help text

This sets the default maximum request size to perform AES requests using software instead of the crypto engine. It can be changed by setting the aes_sw_max_len parameter.

Small blocks are processed faster in software than hardware. Considering the 256-bit ciphers, software is 2-3 times faster than qce at 256-bytes, 30% faster at 512, and about even at 768-bytes. With 128-bit keys, the break-even point would be around 1024-bytes.

The default is set a little lower, to 512 bytes, to balance the cost in CPU usage. The minimum recommended setting is 16-bytes (1 AES block), since AES-GCM will fail if you set it lower. Setting this to zero will send all requests to the hardware.

Note that 192-bit keys are not supported by the hardware and are always processed by the software fallback, and all DES requests are done by the hardware.

Hardware

LKDDb

Raw data from LKDDb:

Sources

This page is automaticly generated with free (libre, open) software lkddb(see lkddb-sources).

The data is retrived from:

Automatic links from Google (and ads)

Custom Search

Popular queries:

Navigation: Linux Kernel Driver DataBase - web LKDDB: main index - C index

Automatically generated (in year 2020). See also LKDDb sources on GitLab