Hi all On 2022-01-17 5:16 pm, dcook@prosentient.com.au wrote:

Great to see another Australian library using Koha!

Yes. We are pleased to be able to use such nice NZ Open Source software.

It looks like you're running Debian Buster (based on your Apache response), so I'm guessing you used the Debian packages to install Koha? I thought that new instances created this way used Plack out of the box, but I think I might be mistaken...

Initial install was Debian packages onto Stretch in 2019. Then an upgrade from Stretch to Buster in September 2021 so thats prob why Plack is not installed.

If you enable Plack/Starman, page loads and search times will be faster, because the application code is run in persistent processes that use pre-loading and caching of code. However, that comes at a cost. In practice, I find each Plack/Starman process reserves about 200-500MB RAM over its lifetime (default 50 requests before it's recycled if I recall correctly), and the default Koha configuration uses 2 Plack/Starman processes. Depending on expected usage, you may want more/fewer Plack/Starman processes. (Note that those processes are shared across the Staff Interface and the OPAC.) Overall, enabling Plack is the best way to improve Koha performance.

(Another thing to note is startup for Plack/Starman processes are CPU resource heavy as a lot of work goes into setting up and verifying the REST API.)

Overall, I'd say the more CPUs the better, especially if you're running your database on the same server.

Yes running on just the one server. Excellent info above, so useful to know this. From that perhaps its better to double what I have now to 2 CPUs and 4 GB RAM and then look at adding in plack for better performance again rather than adding in plack now and later doubling CPU and RAM.

I think Memcached might technically be optional, but you'll want to keep it for performance. Without it, performance would certainly degrade.

OK.

In terms of metrics, you can use third-party log analyzers (for the Apache logs) and web analytics (eg Google Analytics) to get an overview of how the application is performing overall. For more targeted analysis, I tend to just use the Developer Tools in the browser. For instance, I see your OPAC is taking about 4 seconds to serve the homepage. I tried one of the instances I manage (on a high specced server using Plack) and it took 333ms. There are other tools you can use for profiling the application, but that's a something you might want to explore with the "koha-devel" list instead.

Ah! I had forgotten about using developer tools. I have those in my browser and yes I see there is a performance tab which shows lots of load times for components.

More reading: https://lists.katipo.co.nz/public/koha/2020-December/055598.html This said: "I'd say minimum 4 CPU between all the various different Koha subcomponents for any serious usage"

For us I can go to 2 CPUs for now but 4 is a bit too pricy. We can prob go to 4 when we can show how much the library is being used later on :-)

I haven't used Linode so I can't really comment on its features, but other platforms like AWS make it very easy to switch between different CPU and RAM sizes.

Pretty easy. I use AWS also. Going up in a plan is easy as disk is expanded but going down can be a problem if your disk usage no longer fits in the smaller plan.

I'd say your first step is to enable Plack (on your test instance), and just manually compare similar web requests (like loading the home page, performing the same catalogue search). You should already have the RAM to handle it. I could see you getting into strife only having 1 CPU, as that 1 CPU would have a lot of work to do, but that's where the log analysis / web analytics can help you see real life usage.

First step tonight will be to read up on configuring and turning on plack for the test instance. Then I'll toss up doubling cpu/ram before further tests.

I hope that helps. Feel free to send more questions.

Thanks. Much appreciated.

-----Original Message----- Date: Fri, 14 Jan 2022 16:04:11 +1100 From: Mike Lake <mikel@speleonics.com.au> To: Koha <koha@lists.katipo.co.nz> Subject: [Koha] How to measure and improve Koha performance for our instance? Message-ID: <daad1c0c667cacb91cb604a2e7797a9c@speleonics.com.au> Content-Type: text/plain; charset=US-ASCII; format=flowed

Hi all

We have a production library setup at https://opac.caves.org.au and its now ready for users to use. We also have a test instance that can be used for testing. I'm wanting to know the options for measuring and improving the performance - just basic load and search time that users perceive.

Currently we are running on a Linode instance with 1 CPU and 2 GB RAM. Yes it's a small library :-) Looking at Linode Longview it shows we have not hit more than 7% CPU usage and it usually sits at 1% CPU and 670 MB mem when idle. During a query cpu goes to 100% for a short period and mem to ~ 1 GB.

I see in htop that several memcache threads are running. That's now installed automatically with Koha? The wiki seems to suggest that its optional. And there is plack mentioned in the wiki. Should we be running plack?

I can double our Linode instance to 2 CPUs and 4 GB RAM but that's possibly an irreversible change (and double the $) so wish to leave that until I know it would make a significant difference. And how could I quantify that performance increase?

Thanks

-- Mike

-- Mike