openlitespeed server side caching issues

[edmundspriede]

so i am on OpenLiteSpeed 1.7.19

i use m2-crawler.sh script to warm up some pages so i run

./M2-crawler.sh -d https://m50.lv/product-category/gifts/art

and i get response Caching , and Already cached so i see all good so far.

but when i open the link in browser i get miss, which is confusing . on second refresh i will get hit. but it should hit the first time.

what am i missing?

 

[Cold-Egg]

I guess, it's possibly your crawler script hit other cdn nodes.

Once you get a cache hit from "./M2-crawler.sh -d https://m50.lv/product-category/gifts/art ", please try "curl -I https://m50.lv/product-category/gifts/art", then you will see x-qc-pop:xxx which means you have a cache stored on this node, then open your browser and visit the site to check the node name.

 

[edmundspriede]

if fact it was cache vary issue for guest mode. so all is good now

 

[LiteCache]

@edmundspriede

With quic.cloud you can't use M2-crawler.sh to warmup the cache. This script doesn't support CDN usage, so you always warmup the cache at QC node that is closest to the origin server, but not the cache at the origin server. In addition, QC does not support cache varies defined by rewrite rules.

 

[edmundspriede]

yes but it warms up local cache and quic server is aware of it, so it still works

 

[LiteCache]

yes but it warms up local cache and quic server is aware of it, so it still works

Are you sure because this is not technically possible or does the internet work differently in Latvia?

 

[edmundspriede]

ofcourse we have latvian internet

quic cloud show BKD as cache status in this case. so i still get cached page, which is all i care about.
on next refresh i get HIT from quic, but both are cached pages

 

[LiteCache]

If warmup would work with M2-crawler.sh and QC you would get either hit or no status header from origin server, so Latvia don't have a Internet that can switch off gravity.

In M2-crawler.sh there is no code that uses the IP address of the origin host to connect origin host, so curl request goes only to the QC node that is closest to the origin host and only the cache of this QC node is warmed up.

 

[edmundspriede]

this is what i get after M2-crawler. by speed and TTFB it is cached copy.

 

[edmundspriede]

it is obvious request goes to quic node, but quic node will query original server if it does not have a cached page. so what is the difference? original server will get request.

 

[LiteCache]

this is what i get after M2-crawler. by speed and TTFB it is cached copy.

Yes, this confirms what I already tried to make you understandable. x-litespeed-cache header from origin host must be hit if warmup with M2-crawler.sh would work. Warmup of a single QC node doesn't make any sense. Cache at the origin host must be warmed up first to benefit of QC CDN cache and to prevent to provide stale content by QC cache.

 

[edmundspriede]

so what does X-Litespeed-Cache BKD mean?

 

[edmundspriede]

from quic perspective i believe it means , we have no cache but we fetched cached copy from original server so we say BKD. next time we server cached copy with HIT. anyways im tryng to make it work so thaks for help

 

[LiteCache]

BKD === backend
bkd seems to have more than only 1 meaning. e.a if I send a POST request, QC doesn't support caching of POST, but the origin host is able to cache POST, but QC sends bkd header in case of POST.

from quic perspective i believe it means , we have no cache but we fetched cached copy from original server so we say BKD. next time we server cached copy with HIT. anyways im tryng to make it work so thaks for help

No, it means the opposite. Request goes to the origin server, independently what the origin server can do with this request.

....anyways im tryng to make it work so thaks for help

You already have Kitt - The Cache Crawler, so why don't you use it?

 

[edmundspriede]

i use kitt with quic.cloud . so this is exaclty what happens. and the same happens with M2-crawler.
i get BKD after a crawl. and it is a cache hit. so this is all i care about. i can ditch quic CDN at some point

 

[LiteCache]

i use kitt with quic.cloud . so this is exaclty what happens. and the same happens with M2-crawler.
i get BKD after a crawl. and it is a cache hit. so this is all i care about. i can ditch quic CDN at some point

This is technically impossible with M2 crawler and I believe that you are misinterpreting the bkd header.

 

[edmundspriede]

maybe because i have 2nd server without quic, and i use M2 there. but here i have kitt + quic, and it does the job.