Comments and sidebar not showing on one entry

[mdnava]

Whoah. Yeah. That's huge. How much RAM does your SQL DB server have? It should have 16GB or so.

That server has 8GB... Memory doesn't seem to ran out, and, even tho I've setup more of it in mysql there's always between 70% and 30% available memory on peak times.

One thing that seemed to improved performance (less CPU use) was setting up the caching directory in a different hard drive, I did my math based on I/O operations. However, this applies on overall response, because reindexing issues remained the same.

[garvinhicking]

Hi!

That server has 8GB... Memory doesn't seem to ran out, and, even tho I've setup more of it in mysql there's always between 70% and 30% available memory on peak times.

Hm, if you have free memory with that amount of data, there's a configuration problem. You should assign much more key memory to MySQL, currently it only seems to operate on the HDD and not in memory, which leads exactly to your problems with updating data, as the index rows have to be operated on on disc.

HTH,
Garvin

[mdnava]

... You should assign much more key memory to MySQL, currently it only seems to operate on the HDD and not in memory, ...

This is part of my.cnf:

Code: Select all

key_buffer = 500M
myisam_sort_buffer_size = 16M
join_buffer_size = 2M
read_buffer_size = 2M
sort_buffer_size = 3M
table_cache = 3000
thread_cache_size = 200

[garvinhicking]

Hi!

Sadly I'm no expert in mysql configuration parameters; but if you have 8GB RAM, 500M seems small to me, also the other buffers seam very small...maybe you can ask on MySQL specific forums for help?

Regards,
Garvin

[mdnava]

Sadly I'm no expert in mysql configuration parameters; but if you have 8GB RAM, 500M seems small to me, also the other buffers seam very small...maybe you can ask on MySQL specific forums for help?

I did some math for the 500M key buffer size, but I'll try bigger values and I'll let you know the results. The join, read and sort variables seem actually pretty high since they are not global buffers (not a sum), but limits applied to each given query without an index.

[mdnava]

Again, no sidebars or comments in the same entry, spontaneously!.

http://www.venelogia.com/archivos/695/

When I delete simple_cache plugin this issue disapears, is there a known file cache size restriction?

[mdnava]

Hi Garvin,

Just wanted to let you know some things that might help in the future:

1) I've been running Squid as reverse proxy for a week and all issues with high load have disappeared, I getting huge amounts of traffic and server load stays below 1 most of the time.

2) About the blank page issue, in my case I'm certain its caused by cachesimple, just disabling the plugin solves the problem... But still with Squid it needs to be implemented.

3) About comments and sidebars not showing, I'm like 80% certain is also caused by cachesimple but running the reverse proxy seem to have helped, so I'm guessing it was indeed memory related and/or coredumping.

4) About the re-indexing issue consuming too much CPU, I did test changing MySQL key_buffer to higher values (also re-tested upping the other buffers) but performance was the same, and the system had less memory available. With 1GB of key_buffer Apache started swapping and becoming unresponsive at peaks. As I understand the correct value for this setting is at least the sum of the size of all .MYI files on server which in my case its around 50% of 500MB, so I guess that's a good value to keep. Anyways!, with reverse proxy ON this issue has become trivial.

Have a nice day!

[garvinhicking]

Hi!

That's good to know. Yes, cachesimple can in times cache pages with empty content, if the cache-indexing had memory outage or whatever, which lead to empty portions.

Do you maybe have a HOW-TO on how to setup squid as a revery proxy that you could share with other people facing this problem on high-traffic sites?

Regards,
Garvin

[mdnava]

Hello Garvin,

I did take raw notes because HOW-TOs available on the Net where not up-to-date, and, Squid reverse proxy configuration is quite different since 4.6 and 3.0 branches. However, as anyone would guess squid docs are a good starting point, but pretty raw on their own.

I'll make a document out of these notes as soon as I can.

Have a nice day!