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

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1
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0answers
22 views

Linux filesystem page cache - hot or not

How can you tell how much of the filesystem cache is hot (frequently accessed) or not? The use case would be determining when you are approaching the limits of your memory but before you actually hit ...
0
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0answers
11 views

Slowness in constructor of com.mongodb.Response and com.mongodb.DefaultDBDecoder:decode

I'm developing an app and I use mongo to store my data. I have mongo replica set from 5 nodes, I use read preference = true. Also I have good hardware configuration under mongo hosts, but don't use ...
0
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0answers
272 views

Server 2012 slow performance on ESXi 5.5

I'm having performance issues with a virtual Server 2012 that is installed on an ESXi 5.5 (HP-ESXi-5.5.0-iso-5.71.3). The hardware server is an HP ProLiant DL380p Gen8. The server 2012 is acting as ...
0
votes
0answers
7 views

Solr Query thread limit

While performing stress tests of our website, it looks like Solr could be bottleneck. It has enough ram, CPU usage is far from 100%, but we still facing problems of waiting for solr response for even ...
2
votes
2answers
30 views

TCP under OpenVPN is very slow (tsg attached)

I have a very weird problem with OpenVPN. Most VPNs work fine, except this one. Here I get very low performance from TCP connections, but the CPU load is low (so, not a CPU issue). OpenVPN is ...
2
votes
1answer
132 views

mdadm raid10 or nfs performance issues?

I have a fresh mdadm RAID10 device which is healthy, built from 4 x 7200rpm SATA 3 drives: # cat /proc/mdstat Personalities : [raid10] [raid1] md2 : active raid10 sdc3[5] sda3[4] sdb3[1] sdd3[3] ...
-1
votes
1answer
20 views

Innodb performs IO Operation when idle

I am currently doing some stress testing where I am pushing inserts to the database as fast as I can. The simulation inserts 10000 records per second. After inserting around 200 million records I ...
4
votes
3answers
1k views

Why do servers have SAS instead of SSDs? [on hold]

I was wondering why do servers still come with SAS disks instead of SSD disks? I know that SAS are faster than normal hard drives but they are still much slower than SSDs. I think they are more ...
0
votes
1answer
23 views

SCOM alert: The threshold for the Logical Disk\Avg. Disk sec/Transfer performance counter has been exceeded

We are monitoring several Windows Server 2012 R2 VMs running on Hyper-V. Now SCOM (2012 R2 UR2) reports: The threshold for the Logical Disk\Avg. Disk sec/Transfer performance counter has been ...
0
votes
1answer
23 views

How do I know website slowness is related to network or my server

I do know that my php pages generate in less than 0.1 seconds. And also I do know that apache max clients has not been ran out. And website is slowness is confirmed by testing from different ...
0
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0answers
19 views

Nginx : Images takes too long to load. (1sec to download a 50KB image)

I just switched from Apache to debian 7.6 nginx php-fpm and after running all kind of optimisations it seems that it takes a lot longer than usual to display images : The application is extremely ...
7
votes
3answers
2k views

Apache on Win32: Slow Transfers of single, static files in HTTP, fast in HTTPS

I have a weird problem with Apache 2.2.15 on Windows 2000 Server SP4. Basically, I am trying to serve larger static files, images, videos etc. The download seems to be capped at around 550kB/s even ...
-1
votes
1answer
20 views

Child process runs in normal priority only. Why?

I run a scheduled task in Windows Server 2008 R2. I used the technique described here to set its priority to high priority (level 1 of 7). My task runs a process (an EXE file) that creates child ...
0
votes
1answer
35 views

How to speed up QEMU on Windows host?

We want to run our Ubuntu 64bit web server virtualized/emulated on a Windows 64bit host. Intended use is to distribute the VM to customers who might not have "elevated" or "admin" rights on the ...
-1
votes
0answers
28 views

Diagnostic high load sys cpu - low io

A Linux server running Ubuntu 12.04 LTS with LAMP has a strange behaviour since last week: - cpu %sys higher than before, nearly equal %usr (before that, %sys just little compare with %usr) - IO ...
0
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0answers
28 views

clonehd takes 2 hours for a 100GB disk. Expected?

I have a VirtualBox image using VDI and flexible size. Right now the physical DVI file 94GB. The host is an Ubuntu server and the guest is a CentOS 6.4 with ext4 partition. The host is using a sata ...
0
votes
0answers
27 views

Tunning nginx/php5-fpm : why low memory usage with 800 users?

I did optimize nginx with what I found on the internet My specs are 2 servers load balanced : Intel Xeon E5-1620v2 (4c/8t 3,7 GHz+/3,9 GHz+) 32 Go DDR3 ECC 1600MHz 3x 160Go SSD Intel DC S3500 SATA3 ...
11
votes
4answers
5k views

Why VM snapshots are affecting performance?

I read in one of the VMware KB article says that snapshots will directly proportional to VM performance. But my team keep asking me how snapshots can affect performance. I would like to give them ...
3
votes
2answers
37 views

Performance associated with storing millions of files on NTFS

Does anyone have a method / formula, etc that I could use - hopefully based on both current and projected numbers of files - to project the 'right' length of the split and the number of nested ...
0
votes
0answers
10 views

Setting the noatime flag for filesystems inside an lxc container

My host filesystem is ext4 mounted with the noatime flag. But inside an lxc-container, the flag is absent. Here's the output of mount on the host: /dev/sdb1 on /home type ext4 (rw,noatime) And ...
5
votes
4answers
5k views

How can I find out what is causing interrupts on Windows?

Occasionally I come across servers (Windows 2003 and 2008) with high processor % interrupt time. Is there a way to see what program or device is causing the interrupts?
6
votes
0answers
52 views

Fast distributed filesystem for a large amounts of data with metadata in database [on hold]

My project uses several processing machines and one storage machine. Currently storage organized with a MSSQL filetable shared folder. Every file in storage have some metadata in database. Processing ...
5
votes
1answer
206 views

How to distribute files and folders to handle large number of files

I want to manage a huge number of files on my server (say millions). It is needed to save files in two or three levels of folders to keep the number of files in each folder low. On the other hand, it ...
-1
votes
2answers
221 views

High CPU usage on Linux machine

I have a piece of java code running on two different machines, but on one of the linux machines, the code uses a lot of CPU (close to 100% cpu usage). On the other machine the same code uses less cpu ...
1
vote
6answers
4k views

MySQL performance over a (local) network much slower than I would expect

MySQL queries in my production environment are taking much longer than I would expect them too. The site in question is a fairly large Drupal site, with many modules installed. The webserver (Nginx) ...
2
votes
2answers
720 views

About huge page and translation Lookaside Buffer

they confuse me. huge page: the way to manage physical memory of OS kernel, it is split huge page by kernel for reduce the index number in page table. I get it from : ...
3
votes
1answer
335 views

Quantifying the effects of partition mis-alignment

I'm experiencing some significant performance issues on an NFS server. I've been reading up a bit on partition alignment, and I think I have my partitions mis-aligned. I can't find anything that ...
0
votes
0answers
17 views

How to improve the speed of FTP directory listing with proftpd on Debian 7.5?

I install proftpd on a VPS running Debian 7.5 hosted on Linode.com. The server location is in California (US) while I am remoting from Singapore. The server is on SSD and I am using ADSL 100Mbs ...
0
votes
2answers
1k views

Is it possible to use SSD for storage on Windows Azure?

There is some marketing-speak suggesting that it may be possible ..: http://gigaom.com/2012/06/05/new-windows-azure-goes-all-ssd-to-one-up-amazon-in-the-cloud/ .. but I couldn't find any way to ...
7
votes
5answers
4k views

Freebsd or Linux? as BGP router over 100mbps

I am building a server to act as a BGP border router for my 100mbps uplink in ISP. I needs these feature: 1) Dual stack BGP peering/routing (at least 100Mbps, maybe more). 2) Potential full internet ...
2
votes
1answer
975 views

How to improve Varnish performance?

We're experiencing a strange problem with our current Varnish configuration. 4x Web Servers (IIS 6.5 on Windows 2003 Server, each installed on a Intel(R) Xeon(R) CPU E5450 @ 3.00GHz Quad Core, 4GB ...
0
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0answers
7 views

Why perfmon for remote desktop servers get an empty file (only time stamp)?

I'm trying to remotely monitor a server using perfmon, the output file is always empty and only the time stamp field is there?
3
votes
1answer
72 views

Why would zfs performance be bad for moving files within an fs?

On my FreeNAS NAS (9.1.1 running zfs v28), I am getting terrible performance for file moves between two directories in the same raidz fs. Is this expected? How can I fault-find this, if not? The ...
0
votes
1answer
801 views

Performance Issue Between SQL and IIS on Seperate Machines

First time OP on serverfault, but an avid user of stackoverflow. We have two high-specification boxes, both running Windows Server 2008 R2 Standard. On one we have IIS 7.5, the other SQL Server 2008 ...
59
votes
13answers
12k views

Are networks now faster than disks?

This is a software design question I used to work on the following rule for speed cache memory > memory > disk > network With each step being 5-10 times the previous step (e.g. cache ...
6
votes
9answers
5k views

How do I benchmark performance of external DNS lookups?

I'm considering Google's public DNS servers as the external DNS for my network. Currently I'm using the DNS servers from my ISP. I've also considered OpenDNS in the past, but ultimately decided not ...
0
votes
0answers
4 views

Centos running very slow in Virtualbox [migrated]

I am running Centos 7 in Virtualbox 4.3.14. The VM is configured with 2 CPUs 4 GB RAM 3.10.0-123.4.4.el7.x86_64 kernel The host machine is running Windows 7 Pro SP1 64-bit Intel i7-4790 CPU, ...
0
votes
2answers
134 views

Trying to find bottleneck… 60k onsite visitors

I know this will be hard, but I'm willing to try the Q&A route. I have a Wordpress site that currently has 60,000 visitors on the site at once. I'm using an EC2 m3.xlarge, php/php-fpm 5.5.10, ...
-1
votes
1answer
56 views

Google Compute Engine VM performance issue [closed]

we have deployed our portal on Google Compute Engine's VM instance. This is a 2 CPU 13 GB Ram with Debian OS. The link to the deployed site is http://www.beawel.com/UGC (Cloud VM). Our testing server ...
0
votes
0answers
16 views

When I should ignore apr_socket_recv: Connection reset by peer (104) in ab test?

I encountered the well-known apr_socket_recv: Connection reset by peer (104) error during my ab test against my server. But I noticed there is a '-r' option in ab which means Don't exit on ...
2
votes
2answers
2k views

Testing SSL performance on Nginx

I'm running nginx 1.0.0 on CentOS 6 x86_64 with stock OpenSSL. Below are results of openssl benchmarking. sh# openssl speed aes-256-cbc OpenSSL 1.0.0-fips 29 Mar 2010 built on: Sat Jun 25 04:58:15 ...
2
votes
1answer
857 views

BackupExec 12 + RALUS - VERY slow backups

We use Backup Exec 12 and the Remote Agent for Linux/Unix Servers (RALUS) to backup a large RHEL5 system. For various reasons we need to do a daily working set job. These working-set jobs run ...
0
votes
1answer
39 views

ncq not supported on an SATA3.0 HDD in an usb 3.0 casing

is there a well known reason why a SATA3.0 HDD supporting NCQ does not have NCQ queue depth configured when mounted from an usb 3.0 case ? output for hdparm -iI /dev/sda shows NCQ is supported output ...
0
votes
0answers
59 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 ...
0
votes
0answers
14 views

does the number of lvm logical volumes affect ssd performance

Please let me know what your thought are on this. I've installed Ubuntu multiple times on a msata ssd mS200S3 120GB. There is a noticeable decrease of read performance on the exact same hardware for ...
0
votes
0answers
4 views

Poor performance with Ethernet Network Card when transferring files [migrated]

I am having a performance issue I have not been able to solve and hope you guys can help me with it. I bought a NanoPC (small computer with ARM processor) and I have it running Ubuntu 13.10. It has a ...
0
votes
0answers
9 views

How to monitor and alert on a program's resource usage Server 2008?

We have a program that at various times utilizes very high CPU and memory. I would like to create a collection of performance logs of this particular application to see a historical trend over time ...
1
vote
0answers
35 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 - ...
2
votes
2answers
1k views

Changing memory allocator to Jemalloc Centos 6

After reading this blog post about the impact of memory allocators like jemalloc on highly threaded applications, I wanted to test things on a larger scale on some of our cluster of servers. We run ...
1
vote
0answers
57 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. ...