Overload management in an application-based server

An overload manager device for use in a server system, having a service operating in response to input requests, and a server operation parameter related to the operation of said service, said device comprising:

• a monitoring function for evaluating successive values of the server operation parameter as a function of time;
• a first logic function capable of evaluating a first condition, which involves whether the sewer operation parameter passes a first threshold value in a first direction;
• a second logic function capable of evaluating a second condition, which involves whether the sewer operation parameter passes a second threshold value in a second direction, wherein the second condition includes determining that the second direction is opposite to the first direction, and extending from the first threshold value to the second threshold value;
• and
• a request supervisor operable for:
• staffing rejection of the input requests, upon verification of a third condition, wherein the third condition comprises (i) determining a predetermined grace period subsequent to verification of the first condition has elapsed, and (ii) determining the second condition has not been verified during said grace period;
• and
• terminating rejection of the input requests upon verification of a fourth condition related to the verification of said second condition.

A portal server having:

• an overload manager device;
• a service operating in response to input requests;
• and
• a server operation parameter related to the operation of said service;
• wherein said device comprises:
• a monitoring function for evaluating successive values of the server operation parameter as a function of time;
• a first logic function capable of evaluating a first condition, which involves whether the server operation parameter passes a first threshold value in a first direction;
• a second logic function capable of evaluating a second condition, which involves whether the server operation parameter passes a second threshold value in a second direction, wherein the second condition includes determining that the second direction is opposite to the first direction, and extending from the first threshold value to the second threshold value;
• and
• a request supervisor operable for:
• starting rejection of input requests, upon verification of a third condition, wherein the third condition comprises (i) determining a predetermined grace period subsequent to verification of the first condition has elapsed, and (ii) determining the second condition has not been verified during said grace period;
• and
• terminating rejection of the input requests upon verification of a fourth condition related to the verification of said second condition;
• and
• wherein said server operation parameter represents a quantity related to a memory usage in the server.

A computer readable storage medium including program instructions executable to implement a method of managing overload in a server system, having a service operating in response to input requests, and a server operation parameter related to the operation of said service, the method comprising the steps of:

• a. monitoring successive values of the server operation parameter as a function of time,
• b. from such values,
• b1. evaluating a first condition, which involves whether the server operation parameter passes a first threshold value in a first direction, and
• b2. evaluating a second condition, which involves whether the server operation parameter passes a second threshold value in a second direction, wherein the second condition includes determining that the second direction is opposite to the first direction, and extending from the first threshold value to the second threshold value,
• c. starting rejection of input requests, upon verification of a third condition, wherein the third condition comprises (i) determining a predetermined grace period subsequent to verification of the first condition has elapsed, and (ii) determining the second condition has not been verified during said grace period, and
• d. terminating rejection of input requests upon verification of a fourth condition, related to the verification of said second condition.

An overload manager device for use in a server system, having a service operating in response to input requests, and a server operation parameter related to the operation of said service, wherein said device is configured to:

• compare values of the server operation parameter to a first threshold value;
• in response to detecting that the server operation parameter has passed the first threshold value in a first direction:
• compare values of the server operation parameter to a second threshold value, wherein the second threshold value is different from the first threshold value;
• start rejection of input requests, upon determining:
• a predetermined grace period subsequent to detecting the server operation parameter has passed the first threshold value in a first direction has elapsed;
• and
• determining a second condition has not been verified during said grace period, the second condition involving determining whether the sewer operation parameter passes a second threshold value in a second direction, wherein the second condition includes determining that the second direction is opposite to the first direction;
• and
• terminate rejection of input requests in response to detecting the sewer operation parameter has passed the second threshold value in a direction opposite the first direction during the grace period.