System and method for fast file tracking and change monitoring

Abstract

Embodiments are directed towards a dynamic change evaluation mechanism, whereby items having a detected possible change are scheduled for re-evaluation for possible changes at a higher frequency than items detected to not have previously changed, while those items detected as not to have changed are dynamically scheduled for re-evaluation based on an evaluation backlog that may be in turn based, in part, on a time from when an item is assigned an expiration time to when the item is evaluated. In one embodiment, a possibly changed item may be assigned a new expiration time independent of the evaluation backlog. In another embodiment, if no change is detected, then the item may be assigned a new expiration time as a function of a previous expiration time and on the evaluation backlog.

1 . A network device, comprising:
 a transceiver for receiving a plurality of items from one or more client devices over a network; and   a processor for enabling actions, the actions comprising:
 for each item in the plurality of items, assigning an expiration time that indicates when an item is to be scheduled for evaluation to detect a possible change to the item; 
 when an expiration time is detected to have expired for an item, scheduling the item for evaluation; and 
 selecting an item that is scheduled for evaluation, and for the selected item:
 determining a wait time for the selected item that indicates at least a time duration between being scheduled for evaluation and being selected for evaluation, 
 when a possible change is determined for the selected item, setting a new expiration time for scheduling for re-evaluating the selected item for another possible change, the new expiration time being set to at least a minimum expiration time, and 
 when it is determined that the selected item does not include a possible change, setting the new expiration time for scheduling for re-evaluating the selected item for another possible change that is based in part on the expiration time of the selected item and a function of the wait time for the selected item. 
 
   
     
     
         2 . The network device of  claim 1 , wherein when it is determined that the item does not include a possible change, setting the new expiration time to be a value that is larger than a value of an expiration time of an other item that is determined to have a possible change, such that the item is scheduled for re-evaluation at a frequency that is less than a frequency of re-evaluation for the other item. 
     
     
         3 . The network device of  claim 1 , wherein when it is determined that the item does not include a possible change, setting the new expiration time, further comprises:
 when the wait time is determined to be above a threshold value that is based on the expiration time, setting the new expiration time to a value that is based on a multiplicative increase of the expiration time; and   otherwise, setting the new expiration time to be a value that is a decrementing value from the expiration time.   
     
     
         4 . The network device of  claim 1 , wherein when it is determined that the item does not include a possible change, setting the new expiration time, further comprises:
 when the wait time is determined to be above a threshold value that is based on the expiration time, setting the new expiration time to a value that is based on a multiplicative increase of the wait time; and   otherwise, setting the new expiration time to be a value that is a decrementing value from the expiration time.   
     
     
         5 . The network device of  claim 1 , wherein the wait time is configured to represent a time duration consumed by a backlog of other items to be evaluated prior to the item being selected for evaluation. 
     
     
         6 . The network device of  claim 1 , wherein when it is determined that the item does not include a possible change, setting the new expiration time, further comprises:
 employing a plurality of threshold values based on the expiration time, such that each of the plurality of threshold values indicates a different value change of the expiration time; and   when the wait time is determined to be associated with one of the plurality of threshold values, setting the new expiration time to a value that is based on the associated threshold value.   
     
     
         7 . The network device of  claim 1 , wherein determining the wait time for the selected item further indicates a time duration between being assigned an expiration time and being selected for evaluation to detect a possible change. 
     
     
         8 . A method operating on one or more network devices, the method implemented as one or more computer executable instructions for performing actions by the one or more network devices, including:
 receiving a plurality of items from one or more client devices;   for each item in the plurality of items, assigning an expiration time that determines when to schedule for evaluation the respective item to detect a change to the item;   when an expiration time is detected to have expired for an item, scheduling the item for evaluation; and   for each item evaluated, setting a new expiration time for the evaluated item to be re-scheduled for re-evaluation, such that an item having a detected change to the item is scheduled for re-evaluation at a higher frequency over an other item for which a change is undetected for the other item, and wherein the new expiration time of the other item is based in part on a backlog of items scheduled for evaluation prior to evaluation of the other item.   
     
     
         9 . The method of  claim 8 , wherein the new expiration time of the other item for which a change is undetected is based in part on a backlog of items scheduled for evaluation prior to evaluation of the other item, further comprises:
 determining a wait time for the other item that indicates at least a time duration between being scheduled for evaluation and being evaluated; and   setting the new expiration time of the other item based in part on the expiration time of the other item and a function of the wait time for the other item.   
     
     
         10 . The method of  claim 9 , wherein setting the new expiration time of the other item, further comprises:
 when the wait time is determined to be above a threshold value that is based on the expiration time, setting the new expiration time to a value that is based on a multiplicative increase of the expiration time; and   otherwise, setting the new expiration time to be a value that is a decrementing value from the expiration time.   
     
     
         11 . The method of  claim 9 , wherein setting the new expiration time of the other item, further comprises:
 when the wait time is determined to be above a threshold value that is based on the expiration time, setting the new expiration time to a value that is based on a multiplicative increase of the wait time; and   otherwise, setting the new expiration time to be a value that is a decrementing value from the expiration time.   
     
     
         12 . A system, comprising:
 one or more network devices that are configured to provide a tool to one or more client devices, such that the tool enables the one or more client devices to provide a plurality of items; and   one or more other network devices that are configured to receive the plurality of items and to perform actions, the actions comprising:
 for each item in the plurality of items, assigning an expiration time that indicates when an item is to be scheduled for evaluation to detect a possible change to the item; 
 when an expiration time is detected to have expired for an item, scheduling the item for evaluation: and 
 selecting an item that is scheduled for evaluation, and for the selected item:
 determining a wait time for the selected item that indicates at least a time duration between being scheduled for evaluation and being selected for evaluation, 
 when a possible change is determined for the selected item, setting a new expiration time for scheduling for re-evaluating the selected item for another possible change, the new expiration time being set to at least a minimum expiration time, and 
 when it is determined that the selected item does not include a possible change, setting the new expiration time for scheduling for re-evaluating the selected item for another possible change that is based in part on the expiration time of the selected item and a function of the wait time for the selected item. 
 
   
     
     
         13 . The system of  claim 12 , wherein when it is determined that the item does not include a possible change, setting the new expiration time to be a value that is larger than a value of an expiration time of an other item that is determined to have a possible change, such that the item is scheduled for re-evaluation at a frequency that is less than a frequency of re-evaluation for the other item. 
     
     
         14 . The system of  claim 12 , wherein when it is determined that the item does not include a possible change, setting the new expiration time, further comprises:
 when the wait time is determined to be above a threshold value that is based on the expiration time, setting the new expiration time to a value that is based on a multiplicative increase of the expiration time; and   otherwise, setting the new expiration time to be a value that is a decrementing value from the expiration time.   
     
     
         15 . The system of  claim 12 , wherein when it is determined that the item does not include a possible change, setting the new expiration time, further comprises:
 when the wait time is determined to be above a threshold value that is based on the expiration time, setting the new expiration time to a value that is based on a multiplicative increase of the wait time; and   otherwise, setting the new expiration time to be a value that is a decrementing value from the expiration time.   
     
     
         16 . The system of  claim 12 , wherein the wait time is configured to represent a time duration consumed by a backlog of other items to be evaluated prior to the item being selected for evaluation. 
     
     
         17 . The system of  claim 12 , wherein when it is determined that the item does not include a possible change, setting the new expiration time, further comprises:
 employing a plurality of threshold values based on the expiration time, such that each of the plurality of threshold values indicates a different value change of the expiration time; and   when the wait time is determined to be associated with one of the plurality of threshold values, setting the new expiration time to a value that is based on the associated threshold value.   
     
     
         18 . The system of  claim 17 , wherein determining the wait time for the selected item further indicates a time duration between being assigned an expiration time and being selected for evaluation to detect a possible change. 
     
     
         19 . A non-transitory, computer-readable storage device that includes data and instructions, that when installed within on a computer device causes the computer device to perform actions, comprising:
 receiving a plurality of items from one or more client devices;   for each item in the plurality of items, assigning an expiration time that determines when to schedule for evaluation the respective item to detect a change to the item;   when an expiration time is detected to have expired for an item, scheduling the item for evaluation; and   for each item evaluated, setting a new expiration time for the evaluated item to be re-scheduled for re-evaluation, such that an item having a detected change to the item is scheduled for re-evaluation at a higher frequency over an other item for which a change is undetected for the other item, and wherein the new expiration time of the other item is based in part on a backlog of items scheduled for evaluation prior to evaluation of the other item.   
     
     
         20 . The non-transitory, computer-readable storage device of  claim 19 , wherein the new expiration time of the other item for which a change is undetected is based in part on a backlog of items scheduled for evaluation prior to evaluation of the other item, further comprises:
 determining a wait time for the other item that indicates at least a time duration between being scheduled for evaluation and being evaluated; and   setting the new expiration time of the other item based in part on the expiration time of the other item and a function of the wait time for the other item.   
     
     
         21 . The non-transitory, computer-readable storage device of  claim 20 , wherein setting the new expiration time of the other item, further comprises:
 when the wait time is determined to be above a threshold value that is based on the expiration time, setting the new expiration time to a value that is based on a multiplicative increase of the expiration time; and   otherwise, setting the new expiration time to be a value that is a decrementing value from the expiration time.   
     
     
         22 . The non-transitory, computer-readable storage device of  claim 20 , wherein setting the new expiration time of the other item, further comprises:
 when the wait time is determined to be above a threshold value that is based on the expiration time, setting the new expiration time to a value that is based on a multiplicative increase of the wait time; and   otherwise, setting the new expiration time to be a value that is a decrementing value from the expiration time.