From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Chmielewski Subject: Re: SMP-aware kcryptd? Date: Mon, 13 Apr 2009 19:47:16 +0200 Message-ID: <49E37AA4.8060007@wpkg.org> References: <49E3410D.9040500@wpkg.org> <49E37824.8010100@redhat.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <49E37824.8010100@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: device-mapper development Cc: dm-crypt@saout.de List-Id: dm-devel.ids Milan Broz schrieb: > Tomasz Chmielewski wrote: >> Currently, the trend with CPUs is to add more cores rather than increase >> the speed of a single core. >> >> This does not scale very well with certain things in the Linux kernel. >> One of them is kcryptd. >> >> >> A system able to deliver data with a speed of ~200 MB/s from a RAID >> array, will be only able to deliver a fraction of it (i.e. ~40 MB/s in >> my case) when reads are being done from a dm-crypt device. (...) > Anyway, it is not highest priority currently... but still in slow progress. > (but I guess high speed SSDs will increase priority for this too, > currently it is real problem only for RAID arrays:-) And, laptops/netbooks with (slow) multi-core CPUs. Encryption is getting popular there as well. -- Tomasz Chmielewski http://wpkg.org