1. A method for managing allocation of storage in a switch utilizing flow control, the switch comprising a plurality of ports and an internal storage divided into a plurality of storage units, the method comprising:
monitoring an average number of storage units used by each of the plurality of ports over a predetermined time period;
setting a threshold for the average number of storage units used by each of the plurality of ports, the threshold for each port being less than or equal to a total number of storage units assigned to the respective port; and
allocating one or more available storage units assigned to a first of the plurality of ports to a second of the plurality of ports in response to storage allocation management being enabled for the second port and the average number of storage units used by the second port exceeding the threshold for the second port.
2. The method of claim 1, further comprising:
determining whether the threshold for the second port is greater than zero to determine whether storage allocation management is enabled for the second port.
3. The method of claim 1, wherein one or more storage units assigned to the first port are available for allocation when the average number of storage units used by the first port is less than the threshold for the first port or a preset percentage of the threshold for the first port.
4. The method of claim 1, wherein allocating one or more available storage units comprises:
reassigning the one or more available storage units from the first port to the second port; and
updating the total number of storage units assigned to and the threshold for the first port and the second port based on the reassignment of the one or more available storage units.
5. The method of claim 1, further comprising:
reallocating the one or more available storage units from the second port back to the first port when an event occurs.
6. The method of claim 5, wherein the event occurs when a fixed period of time elapses or when the average number of storage units used by the first port reaches the threshold for the first port.
7. A system for managing allocation of storage in switches utilizing flow control, the system comprising:
a switch comprising a plurality of ports and an internal storage divided into a plurality of storage units; and
a controller in communication with the switch, the controller being operable to:
monitor an average number of storage units used by each of the plurality of ports over a predetermined time period,
set a threshold for the average number of storage units used by each of the plurality of ports, the threshold for each port being less than or equal to a total number of storage units assigned to the respective port, and
allocate one or more available storage units assigned to a first of the plurality of ports to a second of the plurality of ports in response to storage allocation management being enabled for the second port and the average number of storage units used by the second port exceeding the threshold for the second port.
8. The system of claim 7, wherein the controller comprises a first controller and a second controller and at least one of the first controller and the second controller is integrated into the switch.
9. The system of claim 8, wherein the first controller is operable to monitor the average number of storage units used by each of the plurality of ports and set the threshold for each of the plurality of ports, and the second controller is operable to allocate the one or more available storage units from the first port to the second port.
10. The system of claim 7, further comprising:
a first register storing the average number of storage units used by each of the plurality of ports;
a second register storing the threshold for each of the plurality of ports; and
a table indicating the port assigned to each of the plurality of storage units,
wherein the first register, the second register, and the table are accessible to the controller.
11. The system of claim 7, wherein the controller is further operable to:
determine whether the threshold for the second port is greater than zero to determine whether storage allocation management is enabled for the second port.
12. The system of claim 7, wherein one or more storage units assigned to the first port are available for allocation when the average number of storage units used by the first port is less than the threshold for the first port or a preset percentage of the threshold for the first port.
13. The system of claim 7, wherein allocate one or more available storage units comprises:
reassign the one or more available storage units from the first port to the second port; and
update the total number of storage units assigned to and the threshold for the first port and the second port based on the reassignment of the one or more available storage units.
14. The system of claim 7, wherein the controller is further operable to:
reallocate the one or more available storage units from the second port back to the first port when a fixed period of time elapses or when the average number of storage units used by the first port reaches the threshold for the first port.
15. A computer program product comprising a computer readable medium, the computer readable medium including a computer readable program for managing allocation of storage in a switch utilizing flow control the switch comprising a plurality of ports and an internal storage divided into a plurality of storage units, wherein the computer readable program when executed on a computer causes the computer to:
monitor an average number of storage units used by each of the plurality of ports over a predetermined time period;
set a threshold for the average number of storage units used by each of the plurality of ports, the threshold for each port being less than or equal to a total number of storage units assigned to the respective port; and
allocate one or more available storage units assigned to a first of the plurality of ports to a second of the plurality of ports in response to storage allocation management being enabled for the second port and the average number of storage units used by the second port exceeding the threshold for the second port.
16. The computer program product of claim 15, wherein the computer readable program when executed on the computer further causes the computer to:
determine whether the threshold for the second port is greater than zero to determine whether storage allocation management is enabled for the second polt.
17. The computer program product of claim 15, wherein one or more storage units assigned to the first port are available for allocation when the average number of storage units used by the first port is less than the threshold for the first port or a preset percentage of the threshold for the first port.
18. The computer program product of claim 15, wherein allocate one or more available storage units comprises:
reassign the one or more available storage units from the first port to the second port; and
update the total number of storage units assigned to and the threshold for the first port and the second port based on the reassignment of the one or more available storage units.
19. The computer program product of claim 15, wherein the computer readable program when executed on the computer further causes the computer to:
reallocate the one or more available storage units from the second port back to the first port when an event occurs.
20. The computer program product of claim 19, wherein the event occurs when a fixed period of time elapses or when the average number of storage units used by the first port reaches the threshold for the first port.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A light source which, when in use, is inserted into a reaction chamber for generating a plasma atmosphere, and which is employed for determining an atom or a molecule density of the plasma atmosphere through an absorption spectroscopy, said light source comprising:
a tubular casing comprising a base portion and tip end;
a cooling medium passage for causing a cooling medium to flow therethrough, the passage being provided along an inner wall of the casing and comprising a supply passage extending from the base portion to a bottom portion disposed near the tip end and a drain passage extending from the bottom portion to the base portion, the supply passage communicating with the drain passage at the bottom portion;
a lens provided at the tip end of the casing;
a first electrode and a second electrode which are provided in the casing and before the lens so as to be vertical to an axis of the casing and parallel to each other;
an insulating spacer provided between the first electrode and the second electrode;
a hole axially penetrating center portions of the first electrode, the insulating spacer, and the second electrode; and
an electric discharge gas passage for introducing an electric discharge gas, along an inner wall of the cooling medium passage, to a back surface of the lens so that the electric discharge gas is reflected by the lens and flows through the hole in a direction of the base portion.
2. A light source according to claim 1, wherein the light source further includes an electrically conductive spring for pressing the second electrode to the insulating spacer, and
wherein a voltage is applied to the second electrode via the spring.
3. A light source according to claim 2, wherein the light source further includes a tubular electrode holder which is axially movably provided in the casing so as to support the first electrode, the insulating spacer, and the second electrode, and to be parallel to the axis of the casing, so that a clearance is provided between an outer wall of the electrode holder and the inner wall of the cooling medium passage and
wherein the clearance and an internal space of the electrode holder serve as the electric discharge gas passage.
4. A light source according to claim 1, wherein the light source further includes a tubular electrode holder which is axially movably provided in the casing so as to support the first electrode, the insulating spacer, and the second electrode, and to be parallel to the axis of the casing, so that a clearance is provided between an outer wall of the electrode holder and the inner wall of the cooling medium passage and
wherein the clearance and an internal space of the electrode holder serve as the electric discharge gas passage.
5. A light source according to claim 1, wherein a plasma is formed in a space between the first electrode and the second electrode.
6. A light source according to claim 1, wherein a plasma is formed in the hole at the first electrode.
7. A light source according to claim 1, further comprising:
an electrode holder inserted into the casing and being movable in an axial direction of the casing to adjust a distance between the first electrode and the lens.
8. A light source according to claim 1, wherein the first electrode comprises a cathode and the second electrode comprises an anode.
9. A light source according to claim 1, further comprising:
a flange facing the second electrode; and
an electrically conductive spring attached to the flange and the second electrode for pressing the second electrode to the insulating spacer.
10. A light source according to claim 9, further comprising:
a power supply for providing an electric discharge from an outside of the reaction chamber to the second electrode via the flange and the electrically conductive spring.
11. A light source according to claim 1, wherein the electric discharge gas passage comprises a space between the lens, the first electrode, and the hole.
12. A light source according to claim 1, wherein the electric discharge gas is aspirated through the hole provided in the first electrode, the insulating spacer, and the second electrode.