Patent JPS5863904A successfully refreshed from Google Patents.
US6438652B1
Expired / Lapsed
US
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Load balancing cooperating cache servers by shifting forwarded request
Assignee: International Business Machines Corp
•
Filing: 1998-10-09
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Granted: 2002-08-20
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Expires: 2018-10-09
Abstract
Abstract In a system including a collection of cooperating cache servers, such as proxy cache servers, a request can be forwarded to a cooperating cache server if the requested object cannot be found locally. An overload condition is detected if for example, due to reference skew, some objects are in high demand by all the clients and the cache servers that contain those hot objects become overloaded due to forwarded requests. In response, the load is balanced by shifting some or all of the forwarded requests from an overloaded cache server to a less loaded one. Both centralized and distributed load balancing environments are described.
Inventors
- 👤 Kevin Michael Jordan
- 👤 Kun-Lung Wu
- 👤 Philip Shi-lung Yu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:58
CPC Classifications
G; G06; G06F; G06F17/00; G06F9/00; G06F9/06; G06F9/46; G06F9/50; G06F9/5005; G06F9/5027; G06F9/505
Claims Analysis
Total Claims: 102
Claim 1
Independent Claim
83 words
A cache server load balancing system, comprising: means for receiving forwarded requests which have been forwarded from one of a plurality of cooperating cache servers in response to a cache miss for an object on the cooperating cache server; and shifting means for shifting one or more of said forwarded requests for the object between cooperating cache servers based on dynamically maintained server load conditions and forwarding frequency, said forwarding frequency comprising the number of times requests for the object have been forwarded.
Claim 2
Dependent Claim
83 words
A cache server load balancing system, comprising: means for receiving forwarded requests which have been forwarded from one of a plurality of cooperating cache servers in response to a cache miss for an object on the cooperating cache server; and shifting means for shifting one or more of said forwarded requests for the object between cooperating cache servers based on dynamically maintained server load conditions and forwarding frequency, said forwarding frequency comprising the number of times requests for the object have been forwarded.
Claim 3
Dependent Claim
54 words
The system of claim 1 , said shifting means further comprising: means for periodically monitoring the load condition on and the forwarding frequency to said cooperating cache servers; and means for proactively shifting one or more subsequent forwarded requests for the cached object from between said cooperating cache servers, in response to said monitoring.
Claim 4
Dependent Claim
26 words
The system of claim 1 , said shifting means further comprising means for checking the load condition and forwarding frequency, in response to the forwarded request.
Claim 5
Dependent Claim
32 words
The system of claim 1 , wherein said shifting means comprises means for modifying an ownership for the object to a shared ownership between two or more of said cooperating cache servers.
Claim 6
Dependent Claim
21 words
The system of claim 4 , further comprising merging said shared ownership in response to a change in the load condition.
Claim 7
Dependent Claim
20 words
The system of claim 1 , further comprising means for locally monitoring the load condition on each cooperating cache server.
Claim 8
Dependent Claim
33 words
The system of claim 6 , further comprising: distributed load monitor means for maintaining a local load condition, the forwarding frequency and ownership information for cached objects on said each cooperating cache server.
Claim 9
Dependent Claim
34 words
The system of claim 7 , further comprising: means for said cooperating cache servers to periodically exchange and maintain one or more of: the load condition information; the forwarding frequency; and the ownership information.
Claim 10
Dependent Claim
44 words
The system of claim 7 , further comprising the steps of: means for said cooperating cache servers to piggyback one or more of: the load condition information; the forwarding frequency; and the ownership information; with one or more of the forwarded requests and responses.
Claim 11
Dependent Claim
42 words
The system of claim 7 , further comprising: means for identifying a less loaded cooperating cache server; and means for communicating one or more of: a shift request; and a copy of the cached object, to said less loaded cooperating cache server.
Claim 12
Dependent Claim
48 words
The system of claim 10 , further comprising: said less loaded cooperating cache server including means for receiving said shift request; and said less loaded cooperating cache server including means for requesting a copy of the object from an originating object server, in response to said shift request.
Claim 13
Dependent Claim
21 words
The system of claim 10 , wherein the copy is obtained via one or more of an intranet, WAN or Internet.
Claim 14
Dependent Claim
46 words
The system of claim 7 , further comprising: a local copy of a caching table on said each cooperating cache server; and means for said cooperating cache servers to maintain the forwarding frequency and the ownership information based on the local copy of the caching table.
Claim 15
Dependent Claim
90 words
The system of claim 7 , further comprising: hash function means for hashing the object space into a number of hash buckets much larger than a total number of said cache servers and assigning said hash buckets to said each cooperating cache server for locating a copy of a locally missed object; and said shifting means comprising means for moving one or more hash buckets from an overloaded server to a less loaded server, effectively changing the hash function so that forwarded requests will not go to said overloaded server.
Claim 16
Dependent Claim
52 words
The system of claim 14 , further comprising: means for modifying the ownership for the object to a shared ownership between at least two of said cooperating cache servers; and means for said cooperating cache servers to forward subsequent object requests to one or more less loaded shared owners of the object.
Claim 17
Dependent Claim
37 words
The system of claim 15 , further comprising: means for detecting a decrease in the load condition for a shared object; and means for merging the shared ownership, in response to the decrease in the load condition.
Claim 18
Dependent Claim
20 words
The system of claim 1 , further comprising: means for updating the forwarding frequency, in response to a forwarded request.
Claim 19
Dependent Claim
34 words
The system of claim 1 , further comprising: multicasting means for multicasting a shift request message to one or more of the other cooperating cache servers so that subsequent forward requests will be shifted.
Claim 20
Dependent Claim
42 words
The system of claim 1 , wherein said shifting means for shifting one or more of said forwarded requests comprises means for communicating a copy of the object from an owning cache server to one or more of said cooperating cache servers.
Claim 21
Dependent Claim
49 words
The system of claim 1 , further comprising, means for calculating the load condition of each cache server in past intervals; means for computing a mean load of all cache servers in past intervals; and means for finding the cache servers that exceed a threshold above said mean load.
Claim 22
Dependent Claim
37 words
The system of claim 1 , wherein the load condition of said cooperating cache server comprises a weighted sum of a count of said forwarded requests, and a count of direct requests to said cooperating cache server.
Claim 23
Dependent Claim
66 words
The system of claim 1 , wherein said object is disposed at an object level and wherein each object may further be one of a plurality of objects in a partition of objects, said partition having a partition level further comprising means for maintaining cache information at one or more of: the object level for each object; and the partition level of a partition of objects.
Claim 24
Dependent Claim
26 words
The system of claim 22 , wherein said cache information of said object level or said partition level, comprises the forwarding frequency associated with the object.
Claim 25
Dependent Claim
27 words
The system of claim 1 , further comprising: centralized logical load monitor means for maintaining the forwarding frequency and the load condition for said cooperating cache servers.
Claim 26
Dependent Claim
16 words
The system of claim 1 , wherein said cooperating cache servers comprise cooperating proxy cache servers.
Claim 27
Dependent Claim
82 words
The system of claim 21 , further comprising: a logical directory server means for locating objects and forwarding requests for locally missed objects; means for maintaining a caching table and a load table, coupled to said directory server; cache server means for interrogating said directory server for object locations in other cache servers for a locally missed object; and directory server means for load balancing requests among said cache servers by manipulating said caching table, in response to requests for object locations.
Claim 28
Dependent Claim
51 words
The system of claim 1 , further comprising: multicasting means on each cache server for multicasting to a list of cooperating cache servers to locate a copy of a locally missed object; said shifting means comprising means for excluding overloaded cache servers from a subset of neighboring cache servers for multicasting.
Claim 29
Dependent Claim
81 words
A cache server load balancing method, comprising the steps of: receiving forwarded requests which have been forwarded from one of a plurality of cooperating cache servers in response to a cache miss for an object on the cooperating cache server; and shifting one or more of said forwarded requests for the object between cooperating cache servers based on dynamically maintained server load conditions and forwarding frequency, said forwarding frequency comprising the number of times requests for the object have been forwarded.
Claim 30
Dependent Claim
81 words
A cache server load balancing method, comprising the steps of: receiving forwarded requests which have been forwarded from one of a plurality of cooperating cache servers in response to a cache miss for an object on the cooperating cache server; and shifting one or more of said forwarded requests for the object between cooperating cache servers based on dynamically maintained server load conditions and forwarding frequency, said forwarding frequency comprising the number of times requests for the object have been forwarded.
Claim 31
Dependent Claim
61 words
The method of claim 28 , said shifting step further comprising the steps of: periodically monitoring the load condition on and the forwarding frequency to an owning cache server; and proactively shifting one or more subsequent forwarded requests for the cached object from the owning cache server to one or more of said cooperating cache servers, in response to said monitoring.
Claim 32
Dependent Claim
27 words
The method of claim 28 , said shifting step further comprising the step of checking the load condition and forwarding frequency, in response to the forwarded request.
Claim 33
Dependent Claim
32 words
The method of claim 28 , wherein said shifting comprises the step of modifying an ownership for the object to a shared ownership between two or more of said cooperating cache servers.
Claim 34
Dependent Claim
23 words
The method of claim 31 , further comprising the step of merging said shared ownership in response to change in the load condition.
Claim 35
Dependent Claim
20 words
The method of claim 28 , further comprising the step of locally monitoring the load on each cooperating cache server.
Claim 36
Dependent Claim
37 words
The method of claim 33 , further comprising the step of: a distributed load monitor monitoring and maintaining a local load condition, the forwarding frequency and ownership information for cached objects on said each cooperating cache server.
Claim 37
Dependent Claim
34 words
The method of claim 34 , further comprising the steps of: said cooperating cache servers periodically exchanging and maintaining one or more of: the load condition information; the forwarding frequency; and the ownership information.
Claim 38
Dependent Claim
43 words
The method of claim 34 , further comprising the steps of: said cooperating cache servers exchanging by piggybacking one or more of: the load condition information; the forwarding frequency; and the ownership information; with one or more of the forwarded requests and responses.
Claim 39
Dependent Claim
20 words
The method of claim 28 , further comprising the step of: receiving a forwarded request and updating the forwarding frequency.
Claim 40
Dependent Claim
41 words
The method of claim 34 , further comprising the steps of: identifying a less loaded cooperating cache server; and communicating one or more of: a shift request; and a copy of the cached object, to said less loaded cooperating cache server.
Claim 41
Dependent Claim
45 words
The method of claim 38 , further comprising the steps of: said less loaded cooperating cache server receiving said shift request; and said less loaded cooperating cache server requesting a copy of the object from an originating object server, in response to said shift request.
Claim 42
Dependent Claim
21 words
The method of claim 38 , wherein the copy is obtained via one or more of an intranet, WAN or Internet.
Claim 43
Dependent Claim
34 words
The method of claim 28 , further comprising the step of multicasting a shift request message to one or more of the other cooperating cache servers so that subsequent forward requests will be shifted.
Claim 44
Dependent Claim
55 words
The method of claim 41 , further comprising the step of: the cooperating cache servers maintaining one of a local copy of a caching table and modifying a hash function; and the cooperating cache servers modifying the ownership information by one of: updating a local copy of a caching table; and modifying a hash function.
Claim 45
Dependent Claim
50 words
The method of claim 42 , further comprising the steps of: modifying the ownership for the object to a shared ownership between at least two of said cooperating cache servers; and said cooperating cache servers forwarding subsequent object requests to one or more less loaded shared owners of the object.
Claim 46
Dependent Claim
36 words
The method of claim 43 , further comprising the steps of: detecting a decrease in the load condition for a shared object; and merging the shared ownership, in response to the decrease in the load condition.
Claim 47
Dependent Claim
53 words
The method of claim 28 , wherein said shifting one or more of said forwarded requests comprises the steps of: communicating a copy of the object from an owning cache server to one or more of said cooperating cache servers; and said cooperating cache server receiving and caching the copy of the object.
Claim 48
Dependent Claim
46 words
The method of claim 28 , further comprising the steps of, calculating the load condition of each cache server in past intervals; computing a mean load of all cache servers in past intervals; and finding the cache servers that exceed a threshold above said mean load.
Claim 49
Dependent Claim
38 words
The method of claim 28 , wherein the load condition of said cooperating cache server can be a weighted sum of a count of said forwarded requests, and a count of direct requests to said cooperating cache server.
Claim 50
Dependent Claim
67 words
The method of claim 28 , wherein said object is disposed at an object level and wherein each object may further be one of a plurality of objects in a partition of objects, said partition having a partition level further comprising the step of maintaining cache information at one or more of: the object level for each object; and the partition level of a partition of objects.
Claim 51
Dependent Claim
26 words
The method of claim 48 , wherein said cache information of said object level or said partition level comprises the forwarding frequency associated with the object.
Claim 52
Dependent Claim
33 words
The method of claim 49 , further comprising the step of: a distributed load monitor monitoring and locally maintaining load conditions, forwarding frequency and ownership information for cached objects on each cache server.
Claim 53
Dependent Claim
31 words
The method of claim 50 , further comprising the steps of: said cooperating cache servers periodically exchanging one or more of the load condition, the forwarding frequency and the ownership information.
Claim 54
Dependent Claim
42 words
The method of claim 49 , further comprising the steps of: said cooperating cache servers exchanging by piggybacking one or more of: the load condition; the forwarding frequency; and the ownership information; with one or more of the forwarded requests and responses.
Claim 55
Dependent Claim
109 words
In a collection of cooperating cache servers, where each cache server can receive direct requests and forwarded requests, and upon a cache miss, a request can be forwarded to an owning cache server caching said object, a load balancing method comprising the steps of, monitoring a dynamically maintained load condition and a forwarding frequency for said cooperating cache servers, said forwarding frequency comprising the number of times requests for the object have been forwarded; and shifting one or more forwarded requests, which have already been forwarded, from one cooperating cache server to a second cooperating cache server based on a change in the load condition and the forwarding frequency.
Claim 56
Dependent Claim
109 words
In a collection of cooperating cache servers, where each cache server can receive direct requests and forwarded requests, and upon a cache miss, a request can be forwarded to an owning cache server caching said object, a load balancing method comprising the steps of, monitoring a dynamically maintained load condition and a forwarding frequency for said cooperating cache servers, said forwarding frequency comprising the number of times requests for the object have been forwarded; and shifting one or more forwarded requests, which have already been forwarded, from one cooperating cache server to a second cooperating cache server based on a change in the load condition and the forwarding frequency.
Claim 57
Dependent Claim
53 words
The method of claim 53 , wherein said step of monitoring the load condition comprises the steps of, calculating the load condition of each cache server in past intervals; computing a mean load of all cache servers in past intervals; and finding those cache servers that exceed a threshold above said mean load.
Claim 58
Dependent Claim
38 words
The method of claim 53 , wherein said shifting step can be performed in response to one or more of: said forwarded requests from said cooperating cache servers; and periodically monitoring the load condition and the forwarding frequency.
Claim 59
Dependent Claim
29 words
The method of claim 53 , further comprising the step of a centralized logical load monitor maintaining the forwarding frequency and the load condition for the cooperating cache servers.
Claim 60
Dependent Claim
35 words
The method of claim 53 , wherein the load condition of said cache server can be a weighted sum of: a count of forwarded requests; and a count of direct requests to said cache server.
Claim 61
Dependent Claim
25 words
The method of claim 53 , further comprising the step of maintaining cache information at each object level or at a partition of objects level.
Claim 62
Dependent Claim
31 words
The method of claim 58 , wherein said cache information of the object level or the partition level comprises the forwarding frequency of requests through said load monitor to said object.
Claim 63
Dependent Claim
16 words
The method of claim 53 , wherein said cooperating cache servers comprise cooperating proxy cache servers.
Claim 64
Dependent Claim
65 words
The method of claim 53 , further comprising the steps of: a logical directory server maintaining a caching table and a load table; said cache servers interrogating said directory server for object locations in other cache servers for a locally missed object; and said directory server load balancing requests among said cache servers by manipulating said caching table, in response to requests for object locations.
Claim 65
Dependent Claim
52 words
The method of claim 56 , further comprising the steps of: each cache server multicasting to a list of cooperating cache servers to locate a copy of a locally missed object; and said shifting step comprising the step of excluding overloaded cache servers from a subset of neighboring cache servers for multicasting.
Claim 66
Dependent Claim
102 words
A program storage device readable by a machine, tangibly executable a program of instructions executable by the machine to perform method steps for cache server load balancing, said method steps comprising: receiving forwarded requests which have been forwarded from one of a plurality of cooperating cache servers in response to a cache miss for an object on the cooperating. cache server; and shifting one or more of said forwarded requests for the object between cooperating cache servers based on dynamically maintained server load conditions and forwarding frequency, said forwarding frequency comprising the number of times requests for the object have been forwarded.
Claim 67
Dependent Claim
102 words
A program storage device readable by a machine, tangibly executable a program of instructions executable by the machine to perform method steps for cache server load balancing, said method steps comprising: receiving forwarded requests which have been forwarded from one of a plurality of cooperating cache servers in response to a cache miss for an object on the cooperating. cache server; and shifting one or more of said forwarded requests for the object between cooperating cache servers based on dynamically maintained server load conditions and forwarding frequency, said forwarding frequency comprising the number of times requests for the object have been forwarded.
Claim 68
Dependent Claim
63 words
The program storage device of claim 63 , said shifting step further comprising the steps of: periodically monitoring the load condition on and the forwarding frequency to an owning cache server; and proactively shifting one or more subsequent forwarded requests for the cached object from the owning cache server to one or more of said cooperating cache servers, in response to said monitoring.
Claim 69
Dependent Claim
29 words
The program storage device of claim 63 , said shifting step further comprising the step of checking the load condition and forwarding frequency, in response to the forwarded request.
Claim 70
Dependent Claim
34 words
The program storage device of claim 63 , wherein said shifting comprises the step of modifying an ownership for the object to a shared ownership between two or more of said cooperating cache servers.
Claim 71
Dependent Claim
25 words
The program storage device of claim 66 , further comprising the step of merging said shared ownership in response to change in the load condition.
Claim 72
Dependent Claim
22 words
The program storage device of claim 63 , further comprising the step of locally monitoring the load on each cooperating cache server.
Claim 73
Dependent Claim
39 words
The program storage device of claim 68 , further comprising the step of: a distributed load monitor monitoring and maintaining a local load condition, the forwarding frequency and ownership information for cached objects on said each cooperating cache server.
Claim 74
Dependent Claim
36 words
The program storage device of claim 69 , further comprising the steps of: said cooperating cache servers periodically exchanging and maintaining one or more of: the load condition information; the forwarding frequency; and the ownership information.
Claim 75
Dependent Claim
45 words
The program storage device of claim 69 , further comprising the steps of: said cooperating cache servers exchanging by piggybacking one or more of: the load condition information; the forwarding frequency; and the ownership information; with one or more of the forwarded requests and responses.
Claim 76
Dependent Claim
43 words
The program storage device of claim 69 , further comprising the steps of: identifying a less loaded cooperating cache server; and communicating one or more of: a shift request; and a copy of the cached object, to said less loaded cooperating cache server.
Claim 77
Dependent Claim
47 words
The program storage device of claim 72 , further comprising the steps of: said less loaded cooperating cache server receiving said shift request; and said less loaded cooperating cache server requesting a copy of the object from an originating object server, in response to said shift request.
Claim 78
Dependent Claim
23 words
The program storage device of claim 72 , wherein the copy is obtained via one or more of an intranet, WAN or Internet.
Claim 79
Dependent Claim
22 words
The program storage device of claim 63 , further comprising the step of: receiving a forwarded request and updating the forwarding frequency.
Claim 80
Dependent Claim
36 words
The program storage device of claim 75 , further comprising the step of: multicasting a shift request message to one or more of the other cooperating cache servers so that subsequent forward requests will be shifted.
Claim 81
Dependent Claim
56 words
The program storage device of claim 76 , further comprising the step of: the cooperating cache servers maintaining one of: a local copy of a caching table; and a hash function; and the cooperating cache servers modifying the ownership information by one of: updating the local copy of a caching table; and modifying a hash function.
Claim 82
Dependent Claim
52 words
The program storage device of claim 77 , further comprising the steps of: modifying the ownership for the object to a shared ownership between at least two of said cooperating cache servers; and said cooperating cache servers forwarding subsequent object requests to one or more less loaded shared owners of the object.
Claim 83
Dependent Claim
38 words
The program storage device of claim 78 , further comprising the steps of: detecting a decrease in the load condition for a shared object; and merging the shared ownership, in response to the decrease in the load condition.
Claim 84
Dependent Claim
55 words
The program storage device of claim 63 , wherein said shifting one or more of said forwarded requests comprises the steps of: communicating a copy of the object from an owning cache server to one or more of said cooperating cache servers; and said cooperating cache server receiving and caching the copy of the object.
Claim 85
Dependent Claim
48 words
The program storage device of claim 63 , further comprising the steps of, calculating the load condition of each cache server in past intervals; computing a mean load of all cache servers in past intervals; and finding the cache servers that exceed a threshold above said mean load.
Claim 86
Dependent Claim
40 words
The program storage device of claim 63 , wherein the load condition of said cooperating cache server can be a weighted sum of a count of said forwarded requests, and a count of direct requests to said cooperating cache server.
Claim 87
Dependent Claim
68 words
The program storage device claim 63 , wherein said object is disposed at an object level and wherein each object may further be one of a plurality of objects in a partition of objects, said partition having a partition level further comprising the step of maintaining cache information at one or more of: the object level for each object; and the partition level of a partition of objects.
Claim 88
Dependent Claim
28 words
The program storage device of claim 83 , wherein said cache information of said object level or said partition level, comprises the forwarding frequency associated with the object.
Claim 89
Dependent Claim
35 words
The program storage device of claim 84 , further comprising the step of: a distributed load monitor monitoring and locally maintaining load conditions, forwarding frequency and ownership information for cached objects on each cache server.
Claim 90
Dependent Claim
33 words
The program storage device of claim 85 , further comprising the steps of: said cooperating cache servers periodically exchanging one or more of the load condition, the forwarding frequency and the ownership information.
Claim 91
Dependent Claim
44 words
The program storage device of claim 84 , further comprising the steps of: said cooperating cache servers exchanging by piggybacking one or more of: the load condition; the forwarding frequency; and the ownership information; with one or more of the forwarded requests and responses.
Claim 92
Dependent Claim
110 words
A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for cache server load balancing in a collection of cooperating cache servers, where each cache server can receive direct requests and forwarded requests, and upon a cache miss, a request can be forwarded to a cooperating cache server caching said object, said method steps comprising: monitoring a load condition and a forwarding frequency for said cooperating cache servers; and shifting one or more forwarded requests from one cooperating cache server to a second cooperating cache server based on a change in the load condition and the forwarding frequency.
Claim 93
Dependent Claim
110 words
A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for cache server load balancing in a collection of cooperating cache servers, where each cache server can receive direct requests and forwarded requests, and upon a cache miss, a request can be forwarded to a cooperating cache server caching said object, said method steps comprising: monitoring a load condition and a forwarding frequency for said cooperating cache servers; and shifting one or more forwarded requests from one cooperating cache server to a second cooperating cache server based on a change in the load condition and the forwarding frequency.
Claim 94
Dependent Claim
57 words
The program storage device of claim 88 , wherein said step of monitoring the load condition comprises the steps of, calculating the load condition of each cache server in past intervals; computing a mean load of all proxy cache servers in past intervals; and finding those proxy cache servers that exceed a threshold above said mean load.
Claim 95
Dependent Claim
40 words
The program storage device of claim 88 , wherein said shifting step can be performed in response to one or more of: said forwarded requests from said cooperating cache servers; and periodically monitoring the load condition and the forwarding frequency.
Claim 96
Dependent Claim
31 words
The program storage device of claim 88 , further comprising the step of a centralized logical load monitor maintaining the forwarding frequency and the load condition for the cooperating cache servers.
Claim 97
Dependent Claim
54 words
The program storage device of claim 91 , further comprising the steps of: each cache server multicasting to a list of cooperating cache servers to locate a copy of a locally missed object; and said shifting step comprising the step of excluding overloaded cache servers from a subset of neighboring cache servers for multicasting.
Claim 98
Dependent Claim
37 words
The program storage device of claim 88 , wherein the load condition of said cache server can be a weighted sum of: a count of forwarded requests; and a count of direct requests to said cache server.
Claim 99
Dependent Claim
65 words
The program storage device of claim 88 , wherein said object is disposed at an object level and wherein each object may further be one of a plurality of objects in a partition of objects, said partition having a partition level further comprising the step of maintaining cache information at the object level for each object; and the partition level of a partition of objects.
Claim 100
Dependent Claim
33 words
The program storage device of claim 88 , wherein said cache information of the object level or the partition level comprises the forwarding frequency of requests through said load monitor to said object.
Claim 101
Dependent Claim
18 words
The program storage device of claim 88 , wherein said cooperating cache servers comprise cooperating proxy cache servers.
Claim 102
Dependent Claim
56 words
The program storage device of claim 88 , further comprising the steps of: maintaining a caching table and a load table; receiving requests for object locations in other cache servers for a locally missed object; and load balancing requests among said cache servers by manipulating said caching table, in response to said requests for object locations.
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USPTO Annuity & Maintenance Windows
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| 7.5 Years (Year 8) | 2009-08-19 | 2010-02-18 | 2010-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-08-19 | 2014-02-18 | 2014-08-20 | $7700.00 | Window Closed / Lapsed |