|
Do you have any formal or informal standards for reasonably achievable SQL query speed? How do you enforce them? Assume a production OLTP database under full realistic production load of a couple dozen queries per second, properly equipped and configured...
Started by le dorfier on
, 4 posts
by 4 people.
Answer Snippets (Read the full thread at stackoverflow):
Transactional and search queries can't be moved off transactional system, so and anything worse like N^2 will eventually ....
95% of search queries (more within 10 seconds.
Of this might be:
95% of transactions to complete within 2 seconds .
|
|
Hey, I'm doing a website that requires me to use about 5 mysql "SELECT * FROM" queries on each site and I'd like to know if it can slow the download speed in any way.
Started by Mike on
, 5 posts
by 5 people.
Answer Snippets (Read the full thread at stackoverflow):
The big question is: how much ....
If you have queries that take a long time to send to the client (where the queries happen), the download speed will depend on how big the content in #2.
Especially if the tables contain lots or rows.
|
|
When I optimize my 2 single queries to run in less than 0.02 seconds and then UNION them the resulting query takes over 1 second to run. Also, a UNION ALL takes longer than a UNION DISTINCT. I would assume allowing duplicates would make the query run ...
Started by Greg on
, 4 posts
by 4 people.
Answer Snippets (Read the full thread at stackoverflow):
Do your queries include ORDER queries separately? I would ....
When I optimize my 2 single queries to run in less than 0.02 seconds and then UNION them the resulting query takes over 1 second to run.
Test this here right now.
|
Ask your Facebook Friends
|
My database queries from Django are starting to take 1-2 seconds and I'm having trouble figuring out why. Not too big a site, about 1-2 requests per second (that hit Django; static files are just served from nginx.)
The thing that confuses me is, I can...
Started by lacker on
, 3 posts
by 3 people.
Answer Snippets (Read the full thread at serverfault):
It will show you the queries you're making on each page load.
Do you use custom SQL queries with Django or have you fetched/robhudson/django-debug-toolbar).
You mean with "exact queries".
|
|
There's ways to get performance graphs with several monitoring software packages out there such as ZenOSS. There's a plugin available that will graph MySQL based SELECT/WRITE/SLOW queries in a nice rrd style graph.
I'm curious if there is a way to also...
Started by imaginative on
, 3 posts
by 3 people.
Answer Snippets (Read the full thread at serverfault):
I use PNP as a quick-and-dirty means of....
You'll still need to use something like perfmon if you want to graph it .
It might suite your needs.
Have a look at http://www.monitoringexchange.org/inventory/Check-Plugins/Database/MySQL/check%5Fmysql%5Fperf.
|
|
Somewhat strange problem... when I start my .NET app for the first time after rebooting my machine, the SQL Server queries are really slow... when I pause the debugger, I notice that it's hanging on getting the response from the query. This only happens...
Started by JoelFan on
, 3 posts
by 3 people.
Answer Snippets (Read the full thread at stackoverflow):
If you run the query....
When you first run a query, SQL generates an execution plan and then caches it.
Most likely you are enjoying the caching affect.
Perhaps TCP/IP is not first in the list.
Check your SQL Server Client Config Settings...
|
|
Recently (in the last few days), my installation of IE8 has been taking 15 to 20 seconds to load my home page. Specifically, the sequence of events (as reported by WireShark) is:-
Browser issues a DNS A query to resolve the home page server's IP address...
Started by MikeJ-UK on
, 7 posts
by 7 people.
Answer Snippets (Read the full thread at serverfault):
Is your computer a domain member, or was it ever?
Those LDAP queries looks a lot like what happens or if it's another process issuing the DNS LDAP queries?
Why does it receive no answer? It's a DNS Query, the lack, maybe 8 queries....
|
|
Somewhat strange problem... when I start my .NET app for the first time after rebooting my machine, the SQL Server queries are really slow... when I pause the debugger, I notice that it's hanging on getting the response from the query. This only happens...
Started by JoelFan on
, 3 posts
by 3 people.
Answer Snippets (Read the full thread at serverfault):
Are you connecting to this machine by IP or hostname?
What happens when you exclusively address this machine by its IP address only? (via connection string or SQL Management Studio)
Check your SQL Client Connection settings (TCP/IP first?)
Add an entry... .
|
|
We've recently started using complied queries in order to improve performance on our Linq to SQL setup. There are several queries that always take multiple seconds to run the first time take under a second in subsequent runs. This appears to be because...
Started by Mykroft on
, 4 posts
by 4 people.
Answer Snippets (Read the full thread at stackoverflow):
The database will be caching 2 things when the SQL is executed:
execution plan data The execution plan will remain in the cache... .
The server need to be the query plan on the first execuation, it then uses the cached plan for subsequent executions.
|
|
We have a query that take takes anywhere from 24-38 seconds to run when you run it from SQL Server Management Studio from a remote machine, but <1 second to run when it is run from the machine locally using SQL Server Management Studio.
SQL Server ...
Started by nvahalik on
, 4 posts
by 4 people.
Answer Snippets (Read the full thread at serverfault):
In another way, like remote desktop etc? If everything is slow when you try to reach Does your query still run just as slow?
Also when you connect remotely is the initial connection slow to connect? My thought here is that....
|
