Eclipse needs a decent amount of heap(Memory | RAM) to work smoothly, minimal heap sizes start from 256 MB RAM and upper limit to that value usually depends on the eclipse plugins and amount of physical RAM installed on your machine.
Chances of eclipse being slow on low heap configuration are high, this is because you are overloading your processor and disk in classic RAM <> Disk swap cycles and CPU processing going on during the same. If this heap falls below a certain level, you might see Eclipse crash with errors like “OutOfMemoryError: Java heap space”.
This post tries to cover a couple of Eclipse flavours/variants and ways to fix performance and memory issues on the same. As Force.com IDE itself is based on Eclipse, so most of the tips apply to Force.com IDE users as well.

How to fix Performance ?

One simple way to boost performance is to use an extremely good configuration machine. But that also not guarantees a good performance if your IDE is not having good defaults. Here are few tips that might help

Too many plugins

Having an Eclipse running with too many un-used plugins doesn’t helps. I have seen developers downloading Eclipse variants with support of lots of languages and features, most of which we usually don’t need. A good example is Force.com IDE, some developers tend to download JEE version of eclipse and install Force.com IDE as a plugin on top of that, this combination is of no use until you are JEE developer your self.
Recommended way is to download the minimal version of eclipse and get the job down with the really required plugins.

• Force.com developers: best bet is to use standalone version of Force.com IDE, which is really a low fat version of Eclipse with the basic required features. I personally use it for all Force.com related development and find it good and better in startup and normal usage speeds.  One can download standalone version from here :http://wiki.developerforce.com/page/Force.com_IDE_Installation
• Java/JEE developers: Their are many options and rich suite of plugins available. You can make best judgement based on nature of your work, mostly JEE version of eclipse would suffice for normal JEE developer, and can be enhanced with good plugins like SVN(Subversive) and Mavens(M2E). But if you are using spring core and plan to opt Spring Tool Suite for the same, you might be making mistake by opting something too heavy that is no where required at all. This doesn’t means STS is a bad tool, make sure you need that STS goodness if you are planning to go for it  

One way that worked best for me is to have a second experimental eclipse installation, that is for experimental use only. For ex. you read about Android development and excitement to develop something makes you install the android plugin for eclipse. If this exercise is done in experimental eclipse installation it would help a lot, as you will be done with your research and in case something goes wrong during plugin installation, your main working eclipse copy is not disturbed at all.

Once you feel that a plugin in experimental installation is of real good use and stable, you can move it to the core Eclipse installation. I know we have un-install plugin feature, but that has messed me a few times by leaving traces of crap.

Too many open projects and files

We end up checking out or creating multiple projects for various clients or own research. Eclipse housekeeping and RAM usage boosts with the number of open projects and files in workspace, a decent boost can be noticed by closing unused projects in workspace. I usually keep multiple eclipse workspaces for various stuff like

• Client projects
• Personal Apps
• Research Projects or Open Source work

Increasing heap size

If you are having a good amount of RAM installed/freely available on your machine, you can ignore the tips above and just boost the Eclipse heap setting to make the most out of the available RAM.
Following table lists various eclipse variants and video tutorials for each to tune the heap size.

Eclipse Variant	OS	Video: How to fix the heap ?
Eclipse standard	Mac
STS (Spring Tool Suite)	Mac
Force.com Standalone IDE	Mac
Force.com Standalone IDE	Windows
Eclipse	Other	Try following the steps in above videos, configuration should be similar Incoming Search:  How to Fix performance and memory issues in Eclipse or Force.com IDE, eclipse ide for salesforce, salesforce development in eclipse, eclipse for salesforce, salesforce eclipse

How add a detail button to your Objects?

Let's imagine that we have a VF page which receive two address URL parameters (From and T0) and show us the driving direction from the "from" address to the "to" address.

Using the page we want to add a detail button to Sales Force Account object called "Driving Direction" and once the Sales Rep click on this button can actually view the driving directions from his office to the client's (Account's) location.

Neat, ha?

So, this is how we go about and do this:

1. Go to "Setup" page (link located on the top right corner of the page)
2. Under the "App Setup" expand the "Customize" item
3. Find Account object and expand it
4. Click on "Buttons and Links"
5. On the "Custom Links and Buttons" section click on "New"
6. Enter Label, Name, Description and Select "Detail Page Button" as type
7. Behavior="Display in new Window" and Content source="URL"
8. Let's imagine that your VF page name is "MapDirections". Then enter the following code into content of the button:

/apex/MapDirections?to={!Account.BillingPostalCode},{!Account.BillingState},{!Account.BillingCountry}&from={!$User.PostalCode},{!$User.State},{!$User.Country}

The above text includes a combination of a URL text and a few tags which later on will be replaced with actual data.

Generally tags follow this format: {!field-name} . You can easily see what field types and field names are available to you using the two dropdown lists provided by Sales Force.

And with this we are done with creating the Detail button however we won't be able to see it on the Account's detail page before we add it into the Account's Layout.

In order to add the button to the Account's layout:

1. Go to: Customize -> Accounts --> Page Layouts
2. Edit any or all page layout on which the Custom Button should be visible
3. Once you click on "Edit" layout button you can view the Account's layout page
4. On the "Button Section" double click on "Detail Buttons"
5. A new window opens up, look at the "Custom Buttons" section your button must be listed there.
6. Add the button to the "Selected Buttons" list and click on.
7. Save the Layout and now you will be able to see your button as it is depicted below:

I have always liked to be able to have one of those fancy AJAX "loading..." messages for my AJAX postback calls. The background screen grays out, all components (textboxes, buttons, etc) become disabled and a little box says "Working on your request..." or "Running..." with that famous GIF animator of a spinning wheel and hey, I finally did it!

In this article I will show how to design the HTML to place the loading message into the center of the screen and gray out the background and the whole nine yards...

In this example I will first create a Visualforce component so that potentially I could use my beautiful "loading..." message on every page I desire, furthermore by forming it as a Component I can parameterize the look and feel of it and easily deploy it into different pages with different coloring styles.

In order to create a new Component click on the "setup" link on the right top corner of the page and find "Develop" item on the left hand-side and expand it, and click on "Components". Alternatively you can browse:
http://yourinstance.salesforce.ccom/apexcomponent/{YourComponentName}

Below you will be to get the code that goes into the component. The HTML code includes two Div elements, one for the gray background and the other for the actual box that the message is shown in and a javascript peice that adjusts the sizes of the div element based on the client browser's resolution and avialable place.

<apex:component >
<!-- Attribute Definitions -->
<apex:attribute name="BorderColor" type="String" required="true" description=""></apex:attribute>
<apex:attribute name="Width" type="String" required="true" description=""></apex:attribute>
<apex:attribute name="Height" type="String" required="true" description=""></apex:attribute>
<apex:attribute name="BackColor" type="String" required="true" description=""></apex:attribute>
<apex:attribute name="BackColor" type="String" required="true" description=""></apex:attribute>
<apex:attribute name="BorderSize" type="String" required="true" description=""></apex:attribute>
<apex:attribute name="ImageUrl" type="String" required="false" description=""></apex:attribute>
<apex:attribute name="Message" type="String" required="false" description=""></apex:attribute>
<apex:attribute name="messageStyle" type="String" required="false" description="Message inline style"></apex:attribute>
<apex:attribute name="BorderStyle" type="String" required="false" description="Message box border style: solid, outset, inset, etc"></apex:attribute>

<div id="salesforceSource_blurybackground" style="position:absolute; left:1px; top:1px; width:100%; height:100%; text-align:center; vertical-align: middle; background-color: #dcdcdc; opacity:0.6;filter:alpha(opacity=60)">
</div>
<div id="salesFroceSource_StatusBox" style="position:absolute; left:100px; top: 100px;width: {!Width}; height:{!Height}; opacity:1;filter:alpha(opacity=100)">
<table border="{!BorderSize}" cellpadding="0" cellspacing="0" style="border-left-color: {!BorderColor};
border-bottom-color: {!BorderColor}; width: {!Width}; border-top-color: {!BorderColor}; height:{!Height};
border-right-color:{!BorderColor}; border-style:{!BorderStyle}; background-color:{!BackColor};">
<tr>
<td align="left" valign="top">
<table border="0" cellpadding="4" cellspacing="0" style="width: 100%; height: 100%">
<tr>
<td style="border-bottom-color:{!BorderColor}; border-bottom-width:1px; border-bottom-style:solid;vertical-align:middle;">
<img src="{!ImageUrl}"/></td>
<td style="border-bottom-color:{!BorderColor}; border-bottom-width:1px; border-bottom-style:solid;vertical-align:middle;{!messageStyle}">
&nbsp;{!Message}</td>
</tr>
</table>
</td>
</tr>
</table>
</div>
<script type="text/javascript">
var AgreementForm = document.getElementById("salesforceSource_blurybackground");
AgreementForm.style.height = window.screen.availHeight + "px";
AgreementForm.style.width = window.screen.availWidth + "px";

var ContainerElem = document.getElementById("salesFroceSource_StatusBox");
//ContainerElem.style.display = "block";
AlignToCenter(ContainerElem);

function AlignToCenter(Element)
{
var availableHeight = 0;
var availableWidth = 0;
if (Element.ownerDocument)
{
var docElement = Element.ownerDocument.documentElement;
availableHeight = parseInt(docElement.clientHeight);
if (availableHeight == "NaN") availableHeight = 0;

availableWidth = parseInt(docElement.clientWidth);
if (availableWidth == "NaN") availableWidth = 0;
}

if (availableHeight == 0 || availableHeight == "NaN")
availableHeight = window.screen.availHeight - 200;
if (availableWidth == 0 || availableWidth == "NaN")
availableWidth = window.screen.availWidth - 100;

var msgBoxTop = parseInt((availableHeight - parseInt(Element.clientHeight))/2);
var msgBoxleft = parseInt((availableWidth - parseInt(Element.style.width))/2);

if (msgBoxTop == "NaN" || msgBoxTop == 0)
msgBoxTop = 100;

Element.style.left = msgBoxleft + "px";
Element.style.top = msgBoxTop + "px";
}
</script>
</apex:component>

Pay a good attention to the Attribute section of the of the component those lines will empower you to change the look of the component entirely!

Ok, Now let's see how we can use this component. In Force.com in order to call your component you will need to call it a prefix tag called "c" and don't ask why because that's the way it is.

<apex:actionStatus id="status">
<apex:facet name="start">
<c:enhancedActionStatus BackColor="#efefef" borderColor="#336699" borderSize="3" height="50px" width="120px" ImageUrl="{!$Resource.AjaxAnimation}" Message="Loading..." messageStyle="color:darkred;font-size:11pt;font-weight:bold;"/>
</apex:facet>
</apex:actionStatus>