1-16. (canceled)
17. A computer readable storage medium having computer code executed by a primary controller in communication with a secondary controller to perform operations, the operations comprising:
retaining modified data for a primary volume as records in a journal, wherein the journal includes records having multiple versions of data;
copying records in the journal to the secondary controller;
receiving a read request to data, wherein multiple versions of the requested data are included in the journal;
determining one of the versions of the requested data to return to the read request;
accessing the determined version of the requested data from the journal to return to the read request.
18. The computer readable storage medium of claim 17, wherein the journal comprises a primary journal, and wherein the records in the primary journal are copied to a secondary journal at the secondary controller.
19. The computer readable storage medium of claim 17, wherein the journal includes information linking records in the journal, wherein a plurality of the records provide different versions of data, wherein the read request is with respect to a point-in-time, wherein the operations further comprise:
processing the linked records in the journal to determine one record having a timestamp as of the point-in-time of the read request.
20. The computer readable storage medium of claim 19, wherein the operations further comprise:
initiating a garbage collection method to remove versions of data from the journal;
processing the linked records to determine journal records having previous versions of data to remove; and
deleting the determined journal records.
21. The computer readable storage medium of claim 19, wherein records in the journal each include headers, wherein the linking information comprises at least one pointer in the headers of versions of data to at least one previous version of the data in the record.
22. The computer readable storage medium of claim 21, wherein the journal includes previous versions of data in sequence.
23. The computer readable storage medium of claim 17, wherein each record includes data for one page and a header, wherein the header includes a number of compressed bytes in the page and a timestamp of the data in the page, and wherein the record and data in the record is stored compressed in the journal.
24. The computer readable storage medium of claim 17, wherein the operations further comprise:
maintaining a directory having pointers pointing to the records;
receiving updated data;
including the updated data in a record included the journal;
update the pointer in the directory to point to the record included in the journal.
25. The computer readable storage medium of claim 24, wherein the directory and journal comprise a primary directory and primary journal, wherein copying records to the secondary journal causes the secondary controller to copy the records to a secondary journal and update a secondary directory to point to the data written to the secondary journal.
26. A system, comprising:
a primary controller having a primary journal;
primary volume accessible to the primary controller;
a secondary controller in communication with the primary controller;
a continuous data protection component executed by the primary controller to perform operations, the operations comprising:
retaining modified data for the primary volume as records in the primary journal, wherein the primary journal includes records having multiple versions of data;
copying records in the primary journal to the secondary controller;
receiving a read request to data, wherein multiple versions of the requested data are included in the primary journal;
determining one of the versions of the requested data to return to the read request; and
accessing the determined version of the requested data from the primary journal to return to the read request.
27. The system of claim 26, wherein the operations performed by the continuous data protection component further comprise copying the records in the primary journal are copied to a secondary journal at the secondary controller.
28. The system of claim 26, wherein the primary journal includes information linking records in the journal, wherein a plurality of the records provide different versions of data, wherein the read request is with respect to a point-in-time, wherein the operations performed by the continuous data protection component further comprise:
processing the linked records in the primary journal to determine one record having a timestamp as of the point-in-time of the read request.
29. The system of claim 28, wherein records in the primary journal each include headers, wherein the linking information comprises at least one pointer in the headers of versions of data to at least one previous version of the data in the record.
30. The system of claim 26, wherein the operations performed by the continuous data protection component further comprise:
maintaining a primary directory having pointers pointing to the records;
receiving updated data;
including the updated data in a record included the primary journal;
update the pointer in the primary directory to point to the record included in the primary journal.
31. The system of claim 30, wherein the secondary controller performs operations, the operations comprising:
writing data to a secondary journal; and
updating a secondary directory to point to the data written to the secondary journal.
32. A method, comprising:
retaining modified data for a primary volume as records in a journal maintained by a primary controller, wherein the journal includes records having multiple versions of data;
copying records in the journal to a secondary controller;
receiving, at the primary controller, a read request to data, wherein multiple versions of the requested data are included in the journal;
determining one of the versions of the requested data to return to the read request;
accessing the determined version of the requested data from the journal to return to the read request.
33. The method of claim 32, the journal comprises a primary journal, and wherein the records in the primary journal are copied to a secondary journal at the secondary controller.
34. The method of claim 32, wherein the journal includes information linking records in the journal, wherein a plurality of the records provide different versions of data, wherein the read request is with respect to a point-in-time, further comprising:
processing the linked records in the journal to determine one record having a timestamp as of the point-in-time of the read request.
35. The method of claim 34, wherein records in the journal each include headers, wherein the linking information comprises at least one pointer in the headers of versions of data to at least one previous version of the data in the record.
36. The method of claim 32, further comprising:
maintaining a directory having pointers pointing to the records;
receiving updated data;
including the updated data in a record included the journal;
update the pointer in the directory to point to the record included in the journal.
37. The method of claim 36, wherein the directory and journal comprise a primary directory and primary journal, further comprising:
writing data, by the secondary controller to the secondary journal; and
updating the secondary directory to point to the data written to the secondary journal.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1-16. (canceled)
17. A method of verifying planarity of a microelectronic component support of a microelectronic component test system with respect to a head of the test system, comprising:
juxtaposing a probe card with a contact surface that is carried by the microelectronic component support, the probe card having probes extending toward the contact surface;
changing a distance along a Z axis between the probe card and the contact surface and recording in a first data set a Z coordinate of the contact surface at which each probe changes a contact condition with respect to a first location on the contact surface;
spacing the probes from the contact surface;
translating at least one of the probe card and the contact surface with respect to an X-Y plane;
thereafter, changing a distance along the Z axis between the probe card and the contact surface and recording in a second data set a Z coordinate of the contact surface at which each probe changes a contact condition with respect to a second location on the contact surface which is spaced from the first location; and
processing the first data set and the second data set with a processor of the test system to determine a planarity characteristic.
18. The method of claim 17 wherein the Z axis is vertical and the X-Y plane is horizontal.
19. The method of claim 17 wherein the contact surface comprises a surface of a contact member and the contact surface has a known planarity, further comprising placing the contact member on the microelectronic component support.
20. The method of claim 17 wherein determining the planarity characteristic comprises quantitatively assessing a relative planarity of the microelectronic component support with respect to the head.
21. The method of claim 17 wherein determining the planarity characteristic comprises determining a maximum planarity deviation.
22. The method of claim 17 further comprising adjusting a support surface of the microelectronic component support in response to the planarity characteristic.
23. The method of claim 17 further comprising adjusting an orientation of the head in response to the planarity characteristic.
24. The method of claim 17 wherein determining the planarity characteristic comprises comparing the first data set and the second data set to determine a planarity of the microelectronic component support.
25. The method of claim 17 wherein determining the planarity characteristic comprises comparing the first data set and the second data set to determine a planarity of the head.
26. The method of claim 17 wherein the first data set comprises a position coordinate of the contact member at which each probe establishes electrical contact with the contact surface.
27. The method of claim 17 wherein the first data set comprises a position coordinate of the contact member at which each probe breaks electrical contact with the contact surface.
28. The method of claim 17 further comprising placing all of the probes of the array in contact with the contact member before recording the change in contact condition and wherein moving the contact member with respect to the contact surface comprises increasing a distance between the head and the microelectronic component support.
29. The method of claim 28 wherein recording the change in contact condition comprises detecting a position of the contact member with respect to the head at which each probe breaks electrical contact with the contact surface.
30. The method of claim 17 wherein juxtaposing the probe card with the contact surface comprises mounting the probe card with ends of the probes arranged in a planar array.
31. The method of claim 17 wherein the probe card is electrically coupled to the head by electrically coupling the probes to head contacts carried by the head.
32. The method of claim 31 further comprising:
removing the probe card from the head;
attaching a test card to the head with test probes of the test card electrically coupled to the head contacts; and
contacting terminals of a microelectronic component with the test probes.
33. The method of claim 32 wherein the first data set and the second data set are processed with a processor of the test system, the method further comprising recording test data for the microelectronic component, and processing the test data with the processor.
34-38. (canceled)