> -----Original Message----- > From: centos-bounces at centos.org > [mailto:centos-bounces at centos.org] On Behalf Of Ali Ahsan > Sent: Monday, May 09, 2011 1:52 PM > To: centos at centos.org > Subject: Re: [CentOS] kswapd taking 100% cpu with no swap on system > > On 05/09/2011 10:46 PM, Brunner, Brian T. wrote: > > > > 50GB in 0.12 ms is 500TB in 1.2 second. > > SATA III buses at 6GB/sec need a "parallelness" of (nearly) > > 100 channels to soak up that data. > > How many drives must be written-to in parallel to sustain that write > > rate is ... Beyond my math skills. > > Its only about Cassandra, not about my system :). SO whats your > suggestion about SATA driver ? My suggestion: That (first) you check your facts. What substantiates a claim of a 50GB/.12ms write-rate? What environment? The claim is (AIUI) utterly misleading. That (IMHO) gross over-statement of Cassandra's write capacity makes any study of your current system a pursuit after feral aquatic fowl. I believe you were after an explanation as to why your kswapd was running 100%? Lets stick to that and not drag in Cassandra vs MySQL. Insert spiffy .sig here: Life is complex: it has both real and imaginary parts. //me ******************************************************************* This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been swept for the presence of computer viruses. www.Hubbell.com - Hubbell Incorporated**