Questions about server hardware and software performance, or network performance.

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8
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0answers
114 views

Why higher await time for DM multipath device than underlying device?

We have a CentOS 6.4 based server attached to Hitachi HNAS 3080 storage and observed the kernel remount the filesystem in read-only mode: May 16 07:31:03 GNS3-SRV-CMP-001 kernel: [1259725.675814] ...
3
votes
0answers
76 views

Windows Server 2003 terminal server extreme logon times

For the past week my users have been experiencing extreme logon times. They are generally in the 20 minute range or more. I will lay out my research below to see if anyone may know how to find the ...
3
votes
0answers
695 views

Troubleshooting Redmine performance

I've got a Redmine instance (Bitnami Stack) that's unusually slow. Because I'm just trying to get to the bottom of this, I have some theories which I'd like to discuss here. So, if anybody has any ...
3
votes
0answers
2k views

Use perfmon to monitor a specific ASP.NET webapp across worker process restarts, IIS restarts, etc.?

I have a few perfmon performance counters that I'd like to track for a specific ASP.NET application over an extended period of time, say a week or a month. The trouble is that perfmon counters are ...
2
votes
0answers
492 views

Cannot set 1G speed on 10G nic using ethtool

I have a linux server with 10G fibre nics: xyz@xyz48:~$ sudo ethtool p1p1 Settings for p1p1: Supported ports: [ FIBRE ] Supported link modes: 10000baseT/Full Supported pause frame use: ...
2
votes
0answers
72 views

“Nosy Neighbor” and the CFQ scheduler

I'm trying to understand how does using CFQ affects the "Nosy Neighbor" problem. I'll ask it a bit naively, can a "Nosy Neighbor" even exist when using CFQ? Isn't that CFQ should make sure all ...
2
votes
0answers
788 views

Sizing of journal disks with Microsoft Storage Spaces parity volume

I'm currently speccing out a new backup server. It's going to be running Windows Server 2012 R2 with Direct Attached Storage, and I'm considering using Storage Spaces rather than using a RAID card. ...
2
votes
0answers
118 views

actual disk iops and write merging

/dev/sdb has LVM and exposes a single logical volume, dm-0. While writing to dm-0, /proc/diskstats reports: # of writes completed sdb 29646717 dm-0 131315099 # of writes merged: sdb 101668283 dm-0 ...
2
votes
0answers
121 views

How to debug sluggish process performance

I have a test application which writes a string to a file 10000 times. I run this on two servers and I get totally different results. [SYSTEM 1] $ time ./test_depth real 0m0.152s user ...
2
votes
0answers
145 views

Infiniband link is at 4X SDR with DDR HCAs; has anyone seen this before?

I've recently upgraded my Infiniband HCAs from SDR to DDR, however upon upgrading, it has not improved the link speed at all. Receiving the following output from 'iblinkinfo': CA: ip-san-1-au3a ...
2
votes
0answers
84 views

IBM xSeries 306 CPU Speed

I have an IBM xSeries 306. The system has been flawless until a week ago. It's a Pentium 4 Dual Core CPU. The CPU speed is 3.20 gHz. Now, it shows 4.26 gHz or 2.16 gHz when the POST screen comes ...
2
votes
0answers
787 views

Amazon RDS: Sudden increase in Read IOPS and Throughput

I am using Amazon RDS to host the databases for my website. I am using the large instances for both my master and my read replica. Everything was running smoothly until suddenly the Read IOPS, Read ...
2
votes
0answers
97 views

IIS 6 About 5% of request are very slow

We have a IIS 6 web server on Win2003 The avg requests/sec = 200 The avg cpu utilization = 30% The memory 10% full HDD avg time = 5% I have turned on the logging to see time-taken for each request ...
2
votes
0answers
89 views

Item count limit in Public Folders?

I'm in the planning phase for a product that is based around an Exchange 2010 (SP2) server, where our items will be stored in public folders. There could be hundreds of thousands of items, and I want ...
2
votes
0answers
147 views

Full Text Search query elapsed time varying wildly

Database Version: Microsoft SQL Server 2005 - 9.00.4035.00 (Intel X86) Nov 24 2008 13:01:59 Copyright (c) 1988-2005 Microsoft Corporation Express Edition with Advanced Services on Windows NT 5.1 ...
2
votes
0answers
80 views

Benchmarking a file server

I'm working on building a new file server... a simple Windows Server box with a few terabytes of disk space to share on the LAN. Pain for current hard drive prices aside :( -- I would like to get ...
2
votes
0answers
65 views

Text entry out of order during slowness Windows Server 2003 terminal server

When the server is running slowly, anything I type in any text entry box comes in out of order. For example, IPCONFIG might become IPFIGCON. Basically, our Windows Server 2003 R2 x64 Terminal Server ...
2
votes
0answers
773 views

ejabberd benchmarks and performance

I'm considering to use XMPP for messaging platform (not a chat, I'd rather use it as a transport protocol) for communicating one to one, one to many between custom clients and I think I will ...
2
votes
0answers
1k views

How can I improve performance over SMB/CIFS for an application that has poor write speeds?

I have a third party application that reads several large files and generates a third large file. Its performance is quite good when the generated file is stored on "local storage", i.e. either a ...
1
vote
0answers
16 views

IIS hanging when running Active Reports, possibly splwow64.exe

We have a Windows 2008 R2 web server running our web app on IIS and when running a particular page which generates a PDF (using Active Reports https://activereports.grapecity.com/) it takes between 1 ...
1
vote
0answers
14 views

What is involved in adding ZFS cache stats to orca?

I am interested in looking to add ZFS cache stats into existing orca performance monitoring that we have. Particularly, I am interested in the output of echo ::memstat | mdb -k Am still in the early ...
1
vote
0answers
30 views

Windows Server 2012 Disk Operations Freezing

I've got 2x brand new Windows server 2012 R2 servers. Fresh install. All Windows updates applied. One on a brand-new physical server, and the other in our VMWare cluster. When I try and perform a ...
1
vote
0answers
48 views

File IO being slow

I've rented this root server with a RAID1 mdadm software raid setup. Using dd to benchmark the file IO speed it achieves 230MB/s write (default blocksize). Certain tasks such as mysql are way slower, ...
1
vote
0answers
55 views

How do I interpret a very high Avg. Disk sec/Write perfmon value?

Short version: Is the perfmon screenshot shown below enough evidence to say "something is wrong with your storage system"? Long version: I am debugging a performance problem: Some SQL Server query ...
1
vote
0answers
28 views

Run application from network drive takes long

This problem started recently, and I wasn't able to find a solution. Not even formatting solved. We have a program on our network drive and the Whole company accesses to this single exe. Usually the ...
1
vote
0answers
101 views

How to interpret atop Disk usage and what disk usage is reasonable

I have a a couple of virtual machines all with the same provider. I'm using them for web hosting and have started to get intermittent slow page load times. I've installed atop to try and get to the ...
1
vote
0answers
75 views

Performance issues with cross-drive NTFS junctions

I have the following setup: Windows 8.1 32-bit Drive 0: system drive, SSD, NTFS, mounted at C:\ Drive 1: data drive, magnetic HDD, NTFS, mounted at C:\Users\Database User\Documents and Z:\ ...
1
vote
0answers
68 views

finding if my linux server is the bottleneck

I have a redhat linux 6.x server being used for writing of backup images by NetBackup before being dedup to tape library. currently, I have at least 20 servers writing to it every time their backup ...
1
vote
0answers
196 views

NGINX using 100% of the server CPU when testing with Blitz.io

I'm facing an issue here and after four days of looking around I decided to ask for some help here, after all a million heads can think a lot better than one. I have a Ubuntu 14.04 server setup with ...
1
vote
0answers
327 views

MongoDB high CPU usage

Running MongoDB 2.4.11 on Ubuntu 14.04.1 LTS In top, this mongod thread is constantly using ~195% CPU: PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 24524 mongodb 20 ...
1
vote
0answers
266 views

Appropriate fan speed for a Dell PowerEdge T710

We have a DELL PowerEdge T710 in our office and it is really really noisy, the fans sound like vacuum cleaners! The discussion is whether the server is malconfigured and can be made more silent or if ...
1
vote
0answers
112 views

Server RAID0: one hdd is more %busy then the others?

I'm testing 3 servers with RAID0 with 4 disks. During my test I noticed on all 3 servers that one of the hdd's is more %busy and has much higher averige IO wait (almost 4x higher then the other ...
1
vote
0answers
277 views

Random server load spikes, number of tasks doubles, CPU/Memory consistent

We run a vBulletin forum with 6,000 visitors per day on an SSD VPS with 5GB RAM and 24 CPU Cores. On a typical day we see 30-50 concurrent users at any given moment. On busy mornings, it'll go up to ...
1
vote
0answers
86 views

Using Azure for application performance testing

I have some custom system management scripts/applications that I would like to performance test against a large number of systems (10,000+) in an effort to simulate larger-scale enterprise networks. ...
1
vote
0answers
409 views

Azure Variable Table v Temp Table

This is a bit long; but I have been working through queries figuring out where a performance issue is coming from. Appreciate you taking the time to read it. I have an application running on a ...
1
vote
0answers
589 views

XenServer 6.2 Read Only and Slow Disk I/O

I virtualized a datacenter a few months back and we have a pool of 3 HP DL360 G5 servers, each with 32GB of Memory and dual Intel Xeons. Recently we have been experiencing 2 issues, the first of which ...
1
vote
0answers
270 views

Network Performance / SMB-CIFS / Guidance

I'm an IT professional working out of my home office. I'm having some performance problems (NAS file copies) which I'm trying to isolate, using iperf. My question is on iperf. Infrastructure - ...
1
vote
0answers
115 views

slow copy due to disk write issue

I am trying to copy a file from /backup/ folder to /backup/abc/ and it is taking a lot of time. The copy operation on performed on other server is pretty fast. # df -HP Filesystem Size Used ...
1
vote
0answers
3k views

MySQL Workbench InnoDB Buffer Usage at 100%, always

The InnoDB Buffer Usage graph is always at 100%. I believe this started to happen when I changed MySQL's temp folder to a much bigger drive, does that make sense? I suppose the thing to do in this ...
1
vote
0answers
93 views

SMI generation / detection in GRUB / real mode vs. in Linux

I'm trying to get an idea of the frequency and duration of SMI events on a Supermicro X10SAE C226 board (2.0a BIOS) with E3-1245v3 Haswell CPU. The Intel BIOS Implementation Test Suite (BITS) SMI ...
1
vote
0answers
67 views

IRQ not handled by all CPUs

I have a problem about balancing irq. I took irq numbers from /etc/interrupts and assigned each irq to each of 24 CPUs as this tutorial says for i in {143..166};do cat /proc/irq/${i}/smp_affinity; ...
1
vote
0answers
500 views

apache performance static file

I have a fairly low-budget VPS (1GB RAM + 2 CPU's) to run a few (5 - 10) different small websites (both static and dynamic). These websites have (very) low traffic (average of 500 unique visits for ...
1
vote
0answers
48 views

Frequent CPU spikes on fresh install

I just reinstalled my Server (Windows Server 2008 R2) and after installing MySQL 5.6, the CPU spikes every few seconds: http://s15.postimg.org/dno7ztfjf/cpuspikes.png Even worse than the higher CPU ...
1
vote
0answers
198 views

Debian mail server's Maildir folder with too many files causing disk I/O to go on high load

I have a Debian mail server running Postfix, Courier and Maildir, with disks on EXT3 filesystem. I have noticed that when I use my webmail application (Squirrelmail, in this case). It gets some kind ...
1
vote
0answers
128 views

RAID6 Ubuntu rebuild - how to calculate best parameters for fastest rebuild

I am doing a resync on a RAID6 array and I am looking at some 2 days to complete. I looked here for hints on how to speed it up, but I have, instead, managed to slow it down! HW details are: 10x 4TB ...
1
vote
0answers
294 views

SSD+MDRAID+LVM+KVM results in lower performance than expected

We use kvm for virtualization, the disk images are stored as logical volumes. The logical volumes are stored on a bunch of software-RAID1 (mdadm) arrays composed of Intel DCS3500 SSDs (each array is a ...
1
vote
0answers
230 views

Postfix performance and how to increase my throughput?

What I've read so far: Postfix Tunning Postfix Bottle Neck Analisys The Book of Postfix (chapter 22) I have similar specs to this guy but I'm only able to send about ~1300 emails/hour What I've ...
1
vote
0answers
47 views

How do I reduce server load for a dormant WordPress site using W3 Total Cache?

My current host who did all performance optimization for me has jacked up their price to $1,000/month, so I was forced to move to a new host. The new host charges only $150/month. They give you W3 ...
1
vote
0answers
567 views

Why are pgpgin/s and majflt/s inconsistent in sar -B?

In sar -B ouptut, I would naively expect pgpgin/s to equal majflt/s multiplied by the system page size. From man sar: pgpgin/s Total number of kilobytes the system paged in ...
1
vote
0answers
253 views

Apache AB results: why does adding concurrency not increase requests processed per second?

So I've been trying to use apache ab to benchmark performance, but I'm having trouble understanding why I'm getting these results. FYI, its a PHP app using Zend Framework, mySQL database, and mostly ...