SYSTEM AND METHOD FOR EFFICIENT CONTENT CACHING IN A STREAMING STORAGE
One embodiment of the present invention provides a system for caching content data to a streaming storage in a content-centric network (CCN). The system maintains an in-memory index table. A respective entry in the index table specifies a disk location in the streaming storage. During operation, the system receives a content packet, calculates an index for the content packet based on one or more header fields included in the content packet, maps the calculated index to a corresponding entry in the in-memory index table, writes the content packet into the streaming storage, and updates the mapped entry in the in-memory index table based on a disk location to which the content packet is written.
1 . A computer-executable method for caching content data to a streaming storage in a content-centric network (CCN), the method comprising:
maintaining an in-memory index table, wherein a respective entry in the index table specifies a disk location in the streaming storage;
receiving a content packet;
calculating an index for the content packet based on one or more header fields included in the content packet;
mapping the calculated index to a corresponding entry in the in-memory index table;
writing the content packet into the streaming storage; and
updating the mapped entry in the in-memory index table based on a disk location to which the content packet is written.
2 . The method of claim 1 , further comprising maintaining an in-memory operation buffer configured to reference pending disk operations.
3 . The method of claim 2 , wherein the in-memory operation buffer includes a linked list identifying a set of pending disk operations on a same block in the streaming storage.
4 . The method of claim 1 , wherein the one or more header fields include at least one of: a similarity hash and a forwarding hash.
5 . The method of claim 4 , wherein calculating the index involves hashing a combination of the similarity hash and the forwarding hash to a shorter-length string.
6 . The method of claim 1 , further comprising:
maintaining a tail pointer configured to point to a next available disk location for writing the content packet; and
updating the tail pointer subsequent to writing the content packet in the streaming storage.
7 . The method of claim 1 , wherein the streaming storage includes a plurality of disks, and wherein the respective entry in the index table includes a disk number and a block number.
8 . The method of claim 1 , further comprising:
receiving an interest packet;
calculating an index of the interest packet;
mapping the index of the interest packet to an entry in the in-memory index table;
extracting a disk location from the entry mapped to the index of the interest;
reading content data stored at the extracted disk location; and
returning the content data as a response to the interest packet.
9 . The method of claim 8 , further comprising:
increasing a popularity level associated with the content data; and
in response to determining that the popularity level associated with the content data being higher than a predetermined level, moving the content data to a popular sector within the streaming storage to prevent future over-written of the content data.
10 . An system for caching content data to a streaming storage in a content-centric network (CCN), the system comprising:
a processor; and
a second storage device coupled to the processor and storing instructions which when executed by the processor cause the processor to perform a method, the method comprising:
maintaining an in-memory index table, wherein a respective entry in the index table specifies a disk location in the streaming storage;
receiving a content packet;
calculating an index for the content packet based on one or more header fields included in the content packet;
mapping the calculated index to a corresponding entry in the in-memory index table;
writing the content packet into the streaming storage; and
updating the mapped entry in the in-memory index table based on a disk location to which the content packet is written.
11 . The system of claim 10 , wherein the method further comprises maintaining an in-memory operation buffer configured to reference pending disk operations.
12 . The system of claim 11 , wherein the in-memory operation buffer includes a linked list identifying a set of pending disk operations on a same block in the streaming storage.
13 . The system of claim 10 , wherein the one or more header fields include at least one of: a similarity hash and a forwarding hash.
14 . The system of claim 13 , wherein calculating the index involves hashing a combination of the similarity hash and the forwarding hash to a shorter-length string.
15 . The system of claim 10 , wherein the method further comprises:
maintaining a tail pointer configured to point to a next available disk location for writing the content packet; and
updating the tail pointer subsequent to writing the content packet in the streaming storage.
16 . The system of claim 10 , wherein the streaming storage includes a plurality of disks, and wherein the respective entry in the index table includes a disk number and a block number.
17 . The system of claim 10 , wherein the method further comprises:
receiving an interest packet;
calculating an index of the interest packet;
mapping the index of the interest packet to an entry in the in-memory index table;
extracting a disk location from the entry mapped to the index of the interest;
reading content data stored at the extracted disk location; and
returning the content data as a response to the interest packet.
18 . The system of claim 17 , wherein the method further comprises:
increasing a popularity level associated with the content data; and
in response to determining that the popularity level associated with the content data being higher than a predetermined level, moving the content data to a popular sector within the streaming storage to prevent future over-written of the content data.
19 . A non-transitory computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for caching content data to a streaming storage in a content-centric network (CCN), the method comprising:
maintaining an in-memory index table, wherein a respective entry in the index table specifies a disk location in the streaming storage;
receiving a content packet;
calculating an index for the content packet based on one or more header fields included in the content packet;
mapping the calculated index to a corresponding entry in the in-memory index table;
writing the content packet into the streaming storage; and
updating the mapped entry in the in-memory index table based on a disk location to which the content packet is written.
20 . The computer-readable storage medium of claim 19 , wherein the method further comprises maintaining an in-memory operation buffer configured to reference pending disk operations.
21 . The computer-readable storage medium of claim 20 , wherein the in-memory operation buffer includes a linked list identifying a set of pending disk operations on a same block in the streaming storage.
22 . The computer-readable storage medium of claim 19 , wherein the one or more header fields include at least one of: a similarity hash and a forwarding hash.
23 . The computer-readable storage medium of claim 22 , wherein calculating the index involves hashing a combination of the similarity hash and the forwarding hash to a shorter-length string.
24 . The computer-readable storage medium of claim 19 , wherein the method further comprises:
maintaining a tail pointer configured to point to a next available disk location for writing the content packet; and
updating the tail pointer subsequent to writing the content packet in the streaming storage.
25 . The computer-readable storage medium of claim 19 , wherein the streaming storage includes a plurality of disks, and wherein the respective entry in the index table includes a disk number and a block number.
26 . The computer-readable storage medium of claim 19 , wherein the method further comprises:
receiving an interest packet;
calculating an index of the interest packet;
mapping the index of the interest packet to an entry in the in-memory index table;
extracting a disk location from the entry mapped to the index of the interest;
reading content data stored at the extracted disk location; and
returning the content data as a response to the interest packet.
27 . The computer-readable storage medium of claim 26 , wherein the method further comprises:
increasing a popularity level associated with the content data; and
in response to determining that the popularity level associated with the content data being higher than a predetermined level, moving the content data to a popular sector within the streaming storage to prevent future over-written of the content data.