sam4k

Kmem Cache Alignment

Understanding alignment, object size and objects per cache for special purposes caches in the SLUB allocator.

Overview

Let's take a look a filp, the special purpose cache for struct file, as an example.

Note: I'm using a 5.4 kernel as that's what I had on hand (newer kernels have like struct slab overlay and stuff)

Additional edit: I've simplified things here, focusing on filp, e.g. additional alignment on size and stuff can happen in calculate_sizes(), typically this is just aligning the size to word boundary (??)

Jinmo

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