U4-3957 - Strange performance issue

Created by Kenneth Solberg 02 Jan 2014, 21:55:03 Updated by Kenneth Solberg 03 Jan 2014, 12:37:13

I have a 6.1.6 site (MVC). At ~20k published nodes I noticed a latency in chrome dev tools at about ~80-100ms. At ~10k nodes the latency dropped to ~50ms. I did a trace and it boiled down to a SelectSingleNode (see screenshot).

And now to the funny part, a look at latency for two different page requests: A clocks in at 10ms and B at 50ms. If I now republish B, the latency for a request to that page suddenly drops to 10ms whereas A now clocks in at 50ms. Can someone explain this behavior?

2 Attachments

Comments

Sebastiaan Janssen 02 Jan 2014, 22:34:05

I can't explain that but how does this impact you? I wouldn't call a few milliseconds a "performance" problem to start with.


Kenneth Solberg 02 Jan 2014, 23:20:34

True, not exactly a performance problem, but used the meta tags that described the "thing" best. Just found it odd. It's also worth mentioning that this was a very simple view w/layoutpage and no macros or inline logic. I was expecting <10ms for such.


Sebastiaan Janssen 03 Jan 2014, 11:33:05

Alright, if it had a real impact on (for example) bulk operations I could've understood this as an issue but if the issue is that you have to wait 40 more milliseconds then I'd say you're trying to optimize a little too much.. ;-)

I know we developers tend to think there must be an explanation for everything but sometimes it's better to focus on bigger problems. :) So, I'm going to close this issue, feel free to discuss it further on the forum and if it leads to an actual problem in our code then feel free to re-open it.


Kenneth Solberg 03 Jan 2014, 11:46:54

Okies, I can live with ~50ms base response time before I start adding macros, but keep in mind that it seems to scale relative to content amount. ~50ms @10k nodes, ~100ms @20k nodes ... my guess is ~200ms @40k nodes etc. .. at this point you defenately feel a drop in instantness.


Sebastiaan Janssen 03 Jan 2014, 12:11:27

I don't think there's much we can do about that, it IS actually doing a xpath select on a huge xml document at that point, remember. :) We're working on new caching mechanisms this year, which do still support xpath, but also faster ways of looking through the cache.


Kenneth Solberg 03 Jan 2014, 12:37:13

Awesome! Just what I wanted to hear :-)


Priority: Normal

Type: Performance Problem

State: Closed

Assignee:

Difficulty: Normal

Category: Architecture

Backwards Compatible: True

Fix Submitted:

Affected versions: 6.1.6

Due in version:

Sprint:

Story Points:

Cycle: