In Linux, how to transmit data in DMA mode-Linux Enterprise Application-Linux server application information is described below. We all know that using DMA to transmit data can consume less CPU resources. Therefore, like other operating systems, Linux supports transferring data from hard disks in DMA mode, however, when installing Red Hat, the default options for DMA are Disable. Of course, you can enable it during installation. If the DMA is disable during installation, how can I activate the DMA? By re-compiling the kernel, You can activate the DMA support, but compiling the kernel is obviously too complicated for beginners. The following method activates the DMA support without compiling the kernel.
1. Check whether the DMA option in the system is activated.
Before performing this operation, check whether the hard disk is using DMA to transmit data. Method: Check the/proc/ide/hda/settings file. One row contains using_dma. If the value following using_dma is set to 1, the system supports DMA, the following operations are free of charge. Of course, if you want to disable the DMA function, you need to look at it again :).
The hdparm command in Linux is used for Disk-related operations. hdparm-I/dev/hda can be used to list possible DMA modes supported by IDE, for example:
