similar to: question about disk performance in domU

Hi all, When I ran the experiments to compare an application''s execution time in both a domU (named cctest1) and a native Linux machine (named ccn10), I noticed the application executes faster in domU. The host of the domU (named ccn9) and ccn10 are two nodes of a cluster and they have same hardware configurations. domU (cctest1) is created by exporting loopback files from dom0 on

Dear all, When I debugged the execution performance of an application using strace, I found there are some system calls like open and stat64 which run faster on XenLinux than the standard Linux. The following is the output of running "strace -c /bin/sh -c /bin/echo foo" on both systems. An open call runs averagely 109 usec on standard Linux but only 41 usecs on XenLinux. An stat64

Hi LLVMers, I am a PHD student in CS dept in UIUC, I am doing a project for Vikram's course, it is about PRE. I would like to know why you didn't choose SSAPRE in LLVM, since it seems to be more suitable for LLVM (it can operate directly on SSA form and avoid the conversion between SSA and bit-vector). Can anyone tell me the reason? Xuehai

On Fri, Apr 4, 2008 at 2:38 AM, Bill Wendling <isanbard at gmail.com> wrote: > On Apr 2, 2008, at 10:11 PM, Xuehai Qian wrote: > > Hi LLVMers, > > I am a PHD student in CS dept in UIUC, I am doing a project for > > Vikram's course, it is about PRE. I would like to know why you didn't > > choose SSAPRE in LLVM, since it seems to be more suitable for

On Apr 4, 2008, at 4:51 PM, Daniel Berlin wrote: > On Fri, Apr 4, 2008 at 2:38 AM, Bill Wendling <isanbard at gmail.com> > wrote: >> On Apr 2, 2008, at 10:11 PM, Xuehai Qian wrote: >>> Hi LLVMers, >>> I am a PHD student in CS dept in UIUC, I am doing a project for >>> Vikram's course, it is about PRE. I would like to know why you >>>

Dear all, When I compared the performance of some application on both a Xen domU and a standard linux machine (where domU runs on a similar physical mahine), I notice the application runs faster on the domU than on the physical machine. Instrumenting the application code shows the application spends more time on popen() calls on domU than on the physical machine. I wonder if xenlinux does some

On Apr 2, 2008, at 10:11 PM, Xuehai Qian wrote: > Hi LLVMers, > I am a PHD student in CS dept in UIUC, I am doing a project for > Vikram's course, it is about PRE. I would like to know why you didn't > choose SSAPRE in LLVM, since it seems to be more suitable for LLVM (it > can operate directly on SSA form and avoid the conversion between SSA > and bit-vector). Can

Hi all, I am new to rsync and I apologize in advance if my question is shallow. I write a simple script to use rsync to transfer a big file (~600MB)from a single source to variable number of destinations in a parallel way. When I transfer the file to 4 destination machines, I get X overall transfer time. Then I transfer the same file to 8 destination machines and I get Y overall transfer time.

I am seeing a problem with Dom0 crashing on x86_64 whenever I create a DomU. I''ve done some more testing, and it appears that this problem is somehow related to networking. Dom0 crashes as soon as the networking services are started when DomU is coming up. As an experiment, I brought up DomU without networking, and it stayed up. As soon as I started DomU with networking enabled, however,

Hello, I am trying to filter a data set like below so that the peaks in the Phase value are more obvious and can be identified by a peak finding function following the useful advise of Carl Witthoft. I have written the following for(i in length(data$Phase)){ newphase=if(abs(data$Phase[i+1]-data$Phase[i])>6){ data$Phase[i+1] }else{data$Phase[i] } } I get the following error which I have not

Hi, I'm getting horrible performance on my samba server, and I am unsure of the cause after reading, benchmarking, and tuning. My server is a K6-500 with 43MB of RAM, standard x86 hardware. The OS is Slackware 10.0 w/ 2.6.7 kernel I've had similar problems with the 2.4.26 kernel. I use samba version 3.0.5. I've listed my partitions below, as well as the drive models. I have a

Dear R Helpers, A few weeks ago I asked for some help on how to accomplish modifications to data in a set of data frames. As part of that request I mentioned that I realized that one way to accomplish my goal was to put the data frames together in a list but that I was looking for a way to do it with data frames and a loop because I "believe the better thing is to work df by df for my

I've tried several times to resize one of my ocfs volumes[see emcpowere1 below] I'm on the latest [prod] version of ocfs/ocfs-tools as of 3pm EST on 18JUL04. Per instructions... Take down db, unmount all ocfs drives, use ' tuneocfs -F -S 100G /dev/emcpowere1 ' Supposedly this should work, but I get get.... The size specified, 100G, is larger than the device size, 59G. Aborting.

Hello, I did df -h on my CentOS 6.4 machine. $ df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_ysg-lv_root 47G 8.8G 36G 20% / tmpfs 948M 372K 947M 1% /dev/shm /dev/sda1 485M 62M 398M 14% /boot /dev/mapper/vg_ysg-lv_home 4.6G 2.7G 1.7G 63% /home What I don't understand is why

Polycom 601 with Sip 2.01 Anyone using Sip 2.01? I have upgraded my phones and now presence no longer functions. Buddy list shows all phones online but status does not change when someone is on a call. Also blf does not function. I am using trixbox, 1.67 was working fine on the same box. Any ideas?

On Fri, Apr 4, 2008 at 5:58 PM, Vikram S. Adve <vadve at cs.uiuc.edu> wrote: > On Apr 4, 2008, at 4:51 PM, Daniel Berlin wrote: > > > On Fri, Apr 4, 2008 at 2:38 AM, Bill Wendling <isanbard at gmail.com> > > wrote: > >> On Apr 2, 2008, at 10:11 PM, Xuehai Qian wrote: > >>> Hi LLVMers, > >>> I am a PHD student in CS dept in UIUC,

On Fri, 13 Jan 2006 21:14 , Tomas Florian <tflorian@telus.net> sent: >Hello, > >I''m having trouble with slow IO performance under Xen 2.0.7 with 2.6 >kernel. I''m running 3 physical machine. I did hdparm -tT in my Dom0 on >both servers and this is what I get: <snip> I would check to make sure your kernels have the right ide drivers builtin or as

Hi everybody. I want to identify duplicate numbers and to increase a value of 0.01 for each time that it is duplicated. Example: x=c(1,2,3,5,6,2,8,9,2,2) I want to do this: 1 2 + 0.01 3 5 6 2 + 0.02 8 9 2 + 0.03 2 + 0.04 I am trying to get something like this: 1 2.01 3 5 6 2.02 8 9 2.03 2.04 Actually I just know the way to identify the duplicated numbers rbind(x, duplicated(x) |

Hi 2 all ! I have problems with concurrent filesystem actions on a ocfs2 filesystem which is mounted by 2 nodes. OS=RH5ES and OCFS2=1.2.6 F.e.: If I have a LV called testlv which is mounted on /mnt on both servers and I do a "dd if=/dev/zero of=/mnt/test.a bs=1024 count=1000000" on server 1 and do at the same time a du -hs /mnt/test.a it takes about 5 seconds for du -hs to execute: 270M

Hi, I'm having a problem with ext3 on my system. I'm running 2.4.13 with the appropiate ext3 patch and a software raid array with paritiions as shown below: Filesystem Size Used Avail Use% Mounted on /dev/md5 939M 237M 654M 27% / /dev/md0 91M 22M 65M 25% /boot /dev/md6 277M 8.1M 254M 4% /tmp /dev/md7 1.8G 1.3G