Caching infrastructure

• US 8,825,594 B2
• Filed: 05/08/2008
• Issued: 09/02/2014
• Est. Priority Date: 05/08/2008
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Skaria, Simon, Kannan, Naresh, Clarke, Simon Peter, Bose, Miko Arnab Sakhya Singha, Antos, Christopher J., Knight, Mark Rolland, Carlson, Andrew G., Hedgpeth, Don Adam, Patel, Mitesh Pankaj, Watson, Andrew Sean, Bailor, Jonathan B., Petrova, Elena
• Primary Examiner(s): Mahmoudi, Tony
• Assistant Examiner(s): NGUYEN, MERILYN P
• Application Number:
  US12/117,025
• Publication Number:
  US 20090282041A1
• Time in Patent Office: 2,308 Days
• Field of Search: 707/704, 707/703, 707/608, 707/622, 707/802, 707/812, 707/821, 707/822
• US Class Current: 707/608
• CPC Class Codes: G06Q 10/10 Office automation; Time management

Abstract

Example systems and methods are directed at maintaining and retrieving presence metadata. One example method includes receiving a request from a first client to edit a document file, and sending short-term check out metadata to the first client to begin an editing session. The method also includes writing the transition ID to a transition table stored in a cache, wherein the presence of another transition ID in the cache indicates that a document has switched from a single-client mode to a multi-client mode. An example system includes a processing unit operative to receive a document, the document including short-term check out metadata indicating an editing session has begun, ping a cache to determine if another transition ID is stored in the cache, and send a transition ID to a transition table stored in a cache to switch from a single-client mode to a multi-client mode.

Claims

1. A method for retrieval of presence metadata, the method comprising:

receiving a request from a first client to edit a document file;

sending short-term check out metadata to the first client to begin an editing session; and

writing a transition ID to a transition table stored in a cache, wherein the presence of the transition ID in the cache indicates that a document has switched from a single-client mode to a multi-client mode;

receiving a ping from the first client to determine if the transition ID is in the cache;

if the transition ID is not in the cache,

receiving a plurality of pings from the first client at regular intervals, and

saving the document to a server a plurality of times without incurring reads/writes to a database, and

if the transition ID is in the cache,

receiving a plurality of pings from the first client to collect a lock table from a database to identify a second client, and

in a separate web service request, receiving the second client'"'"'s lock information.

2. The method of claim 1, wherein receiving the second client'"'"'s lock information comprises receiving a ping from the second client.

3. The method of claim 1, wherein switching from the single-client mode to the multi-client mode including a second client further comprises:

attempting to take another short-term lock on the document and seeing that the second client has already received the document;

determining if the multi-client mode is in progress by checking a database.

4. The method of claim 3, further comprising:

if the multi-client mode is not in progress,

sending the document and transition ID to the second client,

writing another transition ID to the transition table, and

writing to the database information indicating the second client has joined the editing session; and

if the multi-client mode is in progress,

sending the document and transition ID to other clients who are part of the editing session, and

writing to the database information indicating the second client has joined the editing session.

5. The method of claim 1 further comprising refreshing the cache by updating the transition table.

6. The method of claim 5, wherein updating the transition table comprises:

pinging the cache to check for the presence of transition ID in the cache; and

if the transition ID is not present in the cache, determining if the cache has been refreshed within a predetermined time interval;

when the cache has been refreshed within the predetermined time interval, respond to the ping from the cache, and

when the cache has not been refreshed within the predetermined time interval, fetch the transition table corresponding to the document'"'"'s content database.

7. The method of claim 1, wherein the ping from the first client is an “

am I alone”

ping.

8. A system including a cache infrastructure for retrieval of presence metadata,the system comprising:

a memory storage unit; and

a processing unit coupled to the memory storage unit, wherein the processing unit is operative to;

receive short-term check out metadata from a first client to begin an editing session for a document;

add a transition ID to the short-term check out metadata;

write the transition ID to a transition table stored in a cache,

switch from a single-client mode to a multi-client mode, wherein switching from the single-client mode to the multi-client mode comprises the processing unit being operative to notice when the first client attempts to take another short-term lock on the document and seeing that that a second client has already received the document;

determine if the multi-client mode is in progress by checking a database;

receive a ping from the first client to determine if the transition ID is in the cache;

if the transition ID is not in the cache,

receive pings from the first client at regular intervals, and

save the document to a server a plurality of times without incurring any reads/writes to the database, and

if the transition ID is in the cache,

receive a ping from the first client to collect a lock table from the database to identify the second client, and

receive the second client'"'"'s lock information by receiving pings that do not carry lock information.

9. The system of claim 8, further comprising the processing unit being operative to:

if the multi-client mode is not in progress,

send the document and transition ID to the second client,

write the transition ID to the transition table, and

write to the database information indicating the second client has joined the editing session; and

if the multi-client mode is in progress,

send the document and transition ID to other clients that are part of the editing session, and

write to the database information indicating the second client has joined the editing session.

10. The system of claim 8, further comprising the processing unit being operative to refresh the cache by updating the transition table.

11. The system of claim 10, wherein updating the transition table comprises the processing unit being operative to:

receive a ping from the first client to check for the presence of transition ID in the cache; and

if the transition ID is not present in the cache, determine if the cache has been refreshed within a predetermined time interval;

if the cache has been refreshed within the predetermined time interval, respond to the ping from the cache, and

if the cache has not been refreshed within the predetermined time interval, fetch the transition table corresponding to the document'"'"'s content database.

12. The system of claim 8, wherein the ping from the first client is an “

am I alone”

ping.

13. A client computer for retrieval of metadata relating to a multi-client editing session, the client computer comprising:

a memory unit; and

a processing unit operative to;

receive a document from a storage device, the document comprising short-term check out metadata indicating an editing session has begun;

ping a cache to determine if another transition ID is stored in the cache; and

send a transition ID to a transition table stored in a cache if the another transition ID is not stored in the cache to switch from a single-client mode to a multi-client mode;

determine if more than one another transition ID is in the cache;

if more than one another transition ID is in the cache, write to a database information indicating a second client has joined the editing session;

refresh the cache by updating the transition table;

wherein updating the transition table comprises the processing unit being operative to;

ping the cache to check for the presence of another transition ID in the cache; and

if the another transition ID is not present in the cache, determine if the cache has been refreshed within a predetermined time interval;

if the cache has been refreshed within the predetermined time interval, respond to the ping from the cache, and

if the cache has not been refreshed within the predetermined time interval, fetch the transition table corresponding to the document'"'"'s content database.

14. The client computer of claim 13, wherein, if the transition ID is not in the cache the processing unit is further operative to:

ping the storage device at regular intervals, and

save the document to the storage device a plurality of times without incurring any reads/writes to a database.

15. The client computer of claim 13, wherein if the another transition ID is in the cache the processing unit is further operative to:

ping the storage device to collect a lock table from a database to identify a first client; and

submit the client'"'"'s lock information in a separate service request.

16. The client computer of claim 15, wherein submitting the first client'"'"'s lock information comprises the processing unit being further operative to submit pings to the storage device.

17. The client computer of claim 13, wherein switching from the single-client mode to the multi-client mode comprising the processing unit being further operative to:

attempt to take another short-term lock on the document; and

see that that a first client has already received the document.

18. The client computer of claim 13, wherein the ping is an “

am I alone”

ping.

19. The client computer of claim 15, wherein the lock table further includes one or more client identifiers.

20. The client computer of claim 19, wherein the one or more client identifiers are associated with one or more data unit locks.