Questions tagged [performance]
Questions about server hardware and software performance, or network performance.
3,202
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Application slowness due to Tomcat waiting for readLatch
we are getting issues reported by our clients that the application is slow at times, while checking the slow requests (using Glowroot) we could find quite a lot of threads getting stuck in org.apache....
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Storing BLOBs in mysql database
There's a lot of opinion about storing BLOBs in a database and I wonder if there is any actual investigation or figures on the matter.
We have an application that stores images related to various ...
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211
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Event log and performance counters correlation
Anyone else often having a need to correlate multiple log sources such as event log or various log files with performance counters when troubleshooting Windows machines?
For example, we had a case of ...
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772
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What is the performance difference between aws EC2 shared, dedicated instance and dedicated host?
I searched the web, but I did not get any information in terms of performance of your application in EC2 for each type of tenancy - shared, dedicated instance and dedicated host. The information that ...
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Forcing Linux (Ubuntu 18.04) to deallocate some cache prior to high priority job
I have a server that periodically has to do a high priority job as quickly as possible. I know before hand when the job will need to run. I want to tell Linux to do all it's housekeeping a few seconds ...
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Is it reasonable to use NFS on a production web server?
Can NFS be reasonably used on production servers as a means of connecting a compute server to a storage server, assuming the connection is over a LAN 1Gbe or 10Gbe connection?
There's obviously some ...
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276
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Docker on OS disk VS docker on dedicated disk
We have 57 rhel servers machines – with version 7.5
The machines have strong HW as 128G memory and 32 CPU ,
We planed to install docker service on all machines , in order to run couple containers on ...
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RDS MySQL Insights: Top Query "commit"
We are trying to reduce the load on our AWS RDS instance by going through the performance insights.
The top SQL statement listed in the insight is "commit":
In particular, the commit ...
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108
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MYSQL vs. InnoDB [closed]
mysqltuner output.
-------- Storage Engine Statistics -----------------------------------------------------------------
[--] Status: +ARCHIVE +BLACKHOLE +CSV -FEDERATED +InnoDB +MEMORY +MRG_MYISAM +...
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disk I/O latency spikes (contains log files from amplify)
Ubuntu 18.04 LTS server, disk is ssd. Application stack is: mongodb, node, nignx and some python.
Server is up 1 month and already had 3 OS disk fails where Ubuntu would go in read only mode. After ...
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Confirming parameters for XFS filesystem and LVM volume striping over 2 ADAPT (RAID6-like) volumes
We are setting up an ADAPT0 (RAID-60-like) configuration for a file server.
We have six disk pools. Each consists of 14 disks and is set up using ADAPT. According to Dell's official white paper, ADAPT ...
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Linux software raid slow until reboot
I am running an debian 10 machine with 3 4tb hdd drives.
Each drive has a 1GB partition for a raid1 for the boot and the rest of the disk is configured as a raid 5 for lvm.
After a while of running I ...
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How to do performance tuning of Apache server?
We have an apache server 2.4.X which we are using as a reverse proxy in front of one Java Application . We have enabled Apache status module Apache Status and we are able to see that number of idle ...
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345
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Syslog servers - what is "normal" throughput? (Windows vs Linux)
Working in an almost Windows only company - and need to set up a syslog server recieving messages from our proxy, firewall and VPN-applicances. For now we have decided to use Kiwi Syslog server, but ...
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SpectreV1 Mitigation Performance profiling
I am trying to measure the system performance when spectreV1 mitigation is on. I am using stress-ng for that. So far I have tested the system with various stressors like cpu, qsort, str, matrix, ...
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Ultra slow upload speeds with SSL
My wordpress website subdomain upload.website.com bypasses cloudflare.
Uploading to https://upload.website.com is extremely slow - 3 - 15 mins for 100mb
However I did some speed tests on the server ...
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How fast is decryption by a YubiKey? [closed]
Do YubiKeys decrypt GPG or SSH/SFTP data directly within themselves? If so, would that cause a bottleneck? Do YubiKeys have accelerated AES hardware that does most of the heavy lifting of decryption?
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How costly are nginx variables?
nginx FAQ Is there a proper way to use nginx variables to make sections of the configuration shorter, using them as macros for making parts of configuration work as templates? ) saying (bold is mine):
...
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Performance of different DIMM modules setups
I am trying to achieve fastest possible DDR3 DIMM modules setup. I have researched available benchmarks, I was able to came to (reasonably satisfactory) resolution between these pairs
1DPC UDIMM vs ...
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775
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Does graphics card affect the server performance
I was wondering does graphics card actually improve the performance of the server or a dedicated cpu is already enough to do the job. If graphic cards capacity is needed how many does it required?
If ...
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Suspicious ksoftirqd_1 process using high cpu [duplicate]
I run this webserver that serves data to a couple of apps. In the last couple of days I have noticed that some requests take some more time than usual, so I did a top to find out what's running and ...
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How to increase amount of concurrent connections in apache2?
I am running into traffic issues as apache 2.4.18 maxes out on concurrent connections:
ps auxf | grep apache2 | wc -l
258
As soon as 258 is reached the server is waiting to serve new connections ...
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805
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Intermittent KVM performance issues causing performance glitches
We are currently hosted on a hosting provider that allows us to set up multiple virtual machines using KVM, where each virtual machine runs on it's own physical box (ie: one hypervisor, one VM with ...
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Performance differences between EXT4 and XFS on kernel 4.15.0-76
OS: Ubuntu 18.04.4 LTS
Kernel version: 4.15.0-76-generic
Storage type: RAID10 (4 x SSD)
Question: is it a bug for this version of kernel? EXT4 run a lot slower when we perform same SQL insert test; ...
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141
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How to find the bottleneck on a virtual server?
I have purchased a cheap virtual server (running with Ubuntu, with 4 virtual? CPUs and guaranteed 8GB RAM, SSD). I started Tomcat8 with my web application (with -Xmx4096m). The startup time is very, ...
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Wrong link speed; what happens if manually set speed using ethtool fails?
I've got a remote xen server and I noticed that the speed link in autoneg is 100 Full Duplex; all my network is 1000 Full Duplex; do you know any reason for this? Ethtool mentions on both my server ...
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Performance Issue
I'm doing some experiments with my application. My application is in a Docker container and it is programmed to send 4 request every second to a web-server. When I host 30 containers on a single ...
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Why are concurrent downloads faster
Many download managers like this, this and this support downloading a file over multiple parallel connections, one per thread.
The concept is that each connection will download one part of the file ...
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Huge MFT and slow performance
I have a Windows Server 2012 R2 with huge MFT and slow performance when listing file in folder. Filesystem is about 350.000 files but in past many millions file was created and delete with crap Backup ...
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How does avgqu-sz size in iostat output relate to r_await and w_await?
Can someone explain what does avgqu-sz mean in the output of iostat? The manual page states like this.
avgqu-sz:
The average queue length of the requests that were issued to the device.
Can ...
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423
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zfs not using full disk I/O
I have setup zfs on a fresh Ubuntu 20.04. But speed seems awfully slow.
The disks can deliver 140 MB/s if run in parallel:
$ parallel -j0 dd if={} of=/dev/null bs=1M count=1000 ::: /dev/disk/by-id/...
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Pages load only when you restart php-fpm
So here's more context in a GIF
Notice how pages do not load on link clicks, but as soon as you run service php7.2-fpm restart it instantly loads the page and like that with every page.
What is ...
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If you have fetched a subdomain, what lookup related performance implications are there for accessing another subdomain on the same TLD?
Consider this example. My browser visits the following URL:
foo.foobar.com
The page on the domain creates an iframe for
bar.foobar.com
Both domains are hosted in AWS Route53 as aliased A records =>...
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DELL PowerEdge R740xd - NUMA - memory performance
I have two physical database servers (both Windows Server 2016):
test server (5 years old):
DELL PowerEdge R730xd, 1x Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz (4C/8T), 192 GB RAM (12x 16GB PC4-...
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How do I know if SSD is the bottleneck in Linux?
I have a database server which uses a Samsung 840 pro disk. The load is constantly higher than usual, even if there is not much activity on the website. So I suspect the disk has worn out. But how can ...
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Monitoring SLA/SLO/SLI using Prometheus
I have done much research about monitoring SLI metrics with Prometheus. I have found only how to monitor a cluster using Kubernetes. I'm hoping to find a response here for simple monitoring.
I also ...
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343
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Is my server drive on SATA2 or SATA3 based on this output?
smartctl output:
# smartctl -a /dev/sda | grep SATA
SATA Version is: SATA 3.1, 6.0 Gb/s (current: 3.0 Gb/s)
dmesg output (empty):
# dmesg | grep SATA
hdparm output:
# hdparm -I /dev/sda | grep ...
user555159
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VPS is slow despite low memory and cpu usages
recently the website hosted on VPS becomes very hard to reach at times, and I am trying to figure out why. I noticed the following things:
CPU and memory usages are very low (always <15% if we sum ...
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Index rollover latency
I have created an ILM policy as follows,
{
"policy": {
"phases": {
"hot": {
"min_age": "0ms",
"actions": {
"rollover": {
"max_docs": 30
},
...
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1
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3k
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Slow RAID performance for Samsung EVO's
So I've been suspecting performance bottlenecks on a Samsung EVO 850 RAID1 for sometime, but honestly been too lazy to look into it. Now I was starting a new home project, involving a Vmware ESXi host ...
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IIS Number of threads worker process for ASP.NET application
TL;DR; Give the worker process more threads!
Background
We have an ASP.NET application that expose a Web API where one of the "endpoints/methods" makes a set of queries to external system (SQL, AD ...
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RAID 50 vs RAID 10 for performance?
I have a server with 6 SSD's and a raid controller card that supports both RAID 10 and RAID 50 the plan is to use this as our Build server. It will be pulling in NPM Packages and many small code files,...
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My.ini issues with server trying to host multiple connections
I am hosting a game server on a dedicated host. all my ini information and screenshots along with my task manager
please assist with this issue
______
# Example MySQL config file for small systems.
#...
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When should we use containerized application on Linux
I would like to create a Linux server but I'm stuck on one question:
How to know when I should use Docker or Lxc for a given application instead of installing it natively ?
For example, on my server ...
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1k
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Strange Azure VM performance Issues
We have 5 VMs on Azure for a customer. All VMs have been running smoothly.
Now since Monday the VM of one of the users is losing performance every day at 4 PM UTC+1 (+-1h). When we have these ...
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AWS Performance Insight Huge Load from "Other" SQL
Engine: MySQL 5.7.26
Looking at my AWS Performance Insight metrics, I noticed that most of my Database load consumes the query marked "Other" Can I check what is hidden under this label?
Screenshot:
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Buy new VPS just for Mysql or upgrade current one and keep the whole stack on the same server [duplicate]
This is not a question about capacity planning, its about mysql performance over local network vs on the same virtual machine (where it needs to share cpu with other processes)
I have a wordpress+...
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728
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Bottleneck identification using iostat, vmstat, mpstat
I am doing some Apache and MySQL performance tests, then upgrading a single component and running tests again to see where the bottlenecks are. I have a local used server warehouse (Tams in Lindon UT) ...
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jdb2 spike every hour for few seconds
I get IO hang up every hour on the exact same time on my Ubuntu 18.04 server.
iotop indicate that jbd2 spike to araong 30% around this time.
The hangup last only few seconds.
I started noticing this ...
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Ceph hardware sizing calculator
I would like to calculate the Hardware sizing for a ceph cluster. There are so few references to the sizing, that I try to get these details here in the community.
E.g. what shall i have depending on
...
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