From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shaw Tong Tan Subject: Re: Status Update : Deployment of DOSEMU Application Server Date: Thu, 30 Oct 2008 19:59:54 -0700 (PDT) Message-ID: <467339.94722.qm@web52510.mail.re2.yahoo.com> References: <23fd749a0810301710g4527b48bn81b943c25b3777f8@mail.gmail.com> Reply-To: shawtan@yahoo.com Mime-Version: 1.0 Return-path: In-Reply-To: <23fd749a0810301710g4527b48bn81b943c25b3777f8@mail.gmail.com> Sender: linux-msdos-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: dosEmu-list Continuation of previous post. A. 100% CPU remedy. Original background 1. test environment Pentium E2180/CentOS 5.2 (32-bit)/DOSEMU+FreeDOS 1.4.0 from website. 2. I found maximum 4 instances on single host, after that random delay and hangs 3. Std OS environment without any modification. To arrive at a solution 1. tried several DOS utilities, example dosidles, even citrix utility 2. I spent weeks trying many combination. Finally I adopted a combined recommendations from list member Joe to run BX200FIX and setting nice value. I added a CPU control as well. Example below EXAMPLE: taskset -c 1 nice -n 19 dosemu run DOSEMU with nice value of 19 on CPU Core number 1. Dualcore CPU core is 0,1 Quad Core is 0,1,2,3 After implementation, I tested up to 6 clipper-based app instances on 1 cpu core and found response reasonable and stable, no random hangs. Based on my assessment of the overall situation, I feel 6 session/cpu-core is the maximum I am willing to commit. Since I have quad-core host now, I am willing to spread the load across to gain a bit of buffer zone. Note that try not to use Core-0 for dosemu because that's the default for OS and system services. The high cache size on Quad Core also help I think in reducing the memory contention issue.