page:

<apex:form id ="myForm">
<apex:inputHidden value="{!value1}" id="theHiddenInput"/> 
<apex:commandLink value="Save" action="{!save}"/> 
<script> 
    document.getElementById('{!$Component.myForm.theHiddenInput}').value= "lalala"; 
</script>

controller:

public String value1{get;set;}
public PageReference save(){
      system.debug('invalue1 ' + value1);
      return null;
}

question:

when i try to submit this form about 30 times, i will meet the value1's value in log is empty 1 time, and also use fiddler to watch form data, also found the theHiddenInput's value is empty. why? a low percentage to lost the hiddeninput value? anyonu meet this issue before?

tks