SET_DMA_RESERVE(9) Memory Management in Linux SET_DMA_RESERVE(9)NAMEset_dma_reserve - set the specified number of pages reserved in the
first zone
SYNOPSIS
void set_dma_reserve(unsigned long new_dma_reserve);
ARGUMENTS
new_dma_reserve
The number of pages to mark reserved
DESCRIPTION
The per-cpu batchsize and zone watermarks are determined by
present_pages. In the DMA zone, a significant percentage may be
consumed by kernel image and other unfreeable allocations which can
skew the watermarks badly. This function may optionally be used to
account for unfreeable pages in the first zone (e.g., ZONE_DMA). The
effect will be lower watermarks and smaller per-cpu batchsize.
COPYRIGHTKernel Hackers Manual 2.6. November 2013 SET_DMA_RESERVE(9)