Questions tagged [cache]

A cache is a mechanism for temporarily storing (caching) data in memory in order to reduce access time to data stored on disk drives.

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What are the pros and cons of using CLIENT_RESULT_CACHE_SIZE and RESULT_CACHE_MODE

I have multiple questions For Oracle Database 11g Release what are the benefits of using CLIENT_RESULT_CACHE_SIZE and RESULT_CACHE_MODE. How will the CLIENT side cache be kept sync if ...
Phani's user avatar
  • 113
19 votes
2 answers

PostgreSQL Index Caching

I'm having difficulty finding 'lay' explanations of how indexes are cached in PostgreSQL, so I'd like a reality check on any or all of these assumptions: PostgreSQL indexes, like rows, live on disk ...
davetapley's user avatar
4 votes
1 answer

Can I partially invalidate the MySQL table cache?

I want to set a fairly large table to MyISAM mode to keep it cached proactively. The table file is approximately 3GB. After several hours, MySQL invalidates the entire table from cache, while < ...
Bas Groot's user avatar
24 votes
3 answers

Is the overhead of frequent query cache invalidation ever worth it?

I'm currently working on a MySQL database where we are seeing a large number of invalidations from the query cache, primarily because of the high number of INSERT, DELETE and UPDATE statements that ...
Craig Sefton's user avatar
3 votes
1 answer

Mysql: Tell InnoDB to keep a specific table or database out of pool/cache?

I have some tables that are used primarily to keep historical data, or that are only used once a day. I do not want any operations on these tables to disrupt the more important tables present in ...
Brett's user avatar
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1 vote
1 answer

Command line switch to disable Coherence?

We have a Java app that happens to have the coherence jar in the path. My application doesn't need it, so I'd like to pass some type of -D variable to the JVM to tell it to ignore coherence, or ...
Mark Bennett's user avatar
1 vote
1 answer

Where do caching servers conceptually fit in my architecture?

Given the simple well-known architecture below: Where (conceptually) does the caching server(s) sit?
A T's user avatar
  • 391
10 votes
3 answers

How to boost performance of virgin queries in MS SQL Server?

I have ASP.NET web site that does it's own independent caching of data and data does not change for long periods of time, so it does not need to query SQL Server second time with same query. I need to ...
alpav's user avatar
  • 255
1 vote
1 answer

how to use mysql temporal cache tables

I took this example from a book where visitors_today is the cache table from visitor_stored. The idea is to store all the visitors per day (visitors_stored) using a cache table. Create table ...
jcho360's user avatar
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3 votes
1 answer

SQL Server Cache population on server / service startup

We have upgraded our SQL Server instance with buckets of RAM, so it can now much more effectively cache . The issue is that it takes time (days) to populate the cache. As far as I understand this is ...
Matt Evans's user avatar
3 votes
2 answers

MySQL cache is not getting hit by subqueries

I noticed something weird on MySQL query_cache behavior and I would like to know if this is a normal behavior. Let's say I have an item table ID | Item ----------- 1 | Item_1 2 | Item_2 3 | ...
Spredzy's user avatar
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1 vote
3 answers

getting error while starting memecached service with ndb engine

i am installed memcached library by following the steps in the internet. now there is a binary file created in bin folder of mysql now i exicuting the command memcached i am getting error like this ...
Deepak M's user avatar
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11 votes
1 answer

Definitive list of steps for SQL Server baseline testing?

Before running a performance test / baseline for an app that uses SQL Server, I want to be able to set the instance to a "clean" state, without restarting the instance. There are steps I tend to ...
Eric Higgins's user avatar
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0 votes
1 answer

getting error while installing memcached_function

now i am working with memcached with mysql cluster 7.2 for that i am installed libevent-1.4.14b-stable.tar.gz memcached-1.4.5.tar.gz libmemcached-0.8.tar.gz then memcached_functions_mysql-0.8.tar....
Deepak M's user avatar
  • 123
9 votes
1 answer

How much memory is a table taking up?

Is there a way to find out how much memory a table is taking up in SQL Server (2005 and greater)? For example, suppose I have a table with 30 million records. I'd like to know how many pages ...
ivanmp's user avatar
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7 votes
2 answers

How to calculate cache misses for PostgreSQL

I'm administering a server where a tool using a PostgreSQL runs. The tool takes care of most PostgreSQL configurations by itself, but I'm observing some performance problems. I could confirm at OS ...
silvavlis's user avatar
  • 171
4 votes
2 answers

MySQL: Is it safe to have a table with multiple millions of rows?

I have a very complex search query to write that will touch many tables, have conditions and joins. For efficiency reasons, I am strongly considering creating a "cache table" where I would maybe once ...
nute's user avatar
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1 vote
1 answer

Different plans or buffers for different connections?

We had an issue in our dev environment where a procedure call timed out from the web server after 30 seconds. I traced the query and ran it manually (same params and all) from SSMS and it executed in ...
Andreas Ågren's user avatar
4 votes
2 answers

Does Oracle cache queries when using a database link

Some vendor told us that we should not use database link between our database and theirs as the queries executed over a database link would not be cached, nor optimized. I can't find any information ...
HeDinges's user avatar
  • 143
1 vote
1 answer

MySQL: How do I limit or prevent caching for specific tables?

I'm currently working on a database schema for tables to hold user information on a website with integrated forums. Right now my idea is to have all the data in two separate tables: one table with "...
jsonnull's user avatar
  • 113
2 votes
2 answers

Functioning of Oracle's Server result Cache

I am reading the Oracle concepts doc and have a doubt [about general cache mechanism ] : PL/SQL function code can include a request to cache its results. Upon invocation of this function, the ...
vettipayyan's user avatar
5 votes
5 answers

Why is MySQL caching data on our dynamic PHP site?

We are having an annoyance with our PHP/MySQL site in that it seems to cache data from the database and our PHP pages are showing out of date records. In fact, there are pages that link to URLs that ...
user1867's user avatar
43 votes
6 answers

PostgreSQL: Force data into memory

Is there a systematic way to force PostgreSQL to load a specific table into memory, or at least read it from disk so that it will be cached by the system?
Adam Matan's user avatar
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