Correlating time on storage network components
A temporal correlation may be determined between times specified according to different time standards on different storage network components. A host system may poll a storage system periodically. In response to each poll request, the storage system may respond with the current time on the storage system (CST) according to the time standard of the storage system. The host system may store temporal correlation information (TCI) associating the CST and the current time on the host system (CHT) according to the time standard of the host system. A data structure (TCT) may be provided, where each entry may specify TCI for a CST/CHT pair, the TCI including the CST, CHT and other information corresponding to the temporal correlation between the pair. The TCI may be used to correlate the time of a phenomenon according to the host system time standard to a time according to the storage system time standard.
1. For a storage network including a first component and a second component, a method comprising:
sending a request from the second component to the first component to provide a current time on the first component, wherein the first and second components are physical components in the storage network;
receiving a response to the request, the response specifying a first time when the response was sent according to a first time standard of the first component;
determining a second time when the response was received according to a second time standard of the second component;
storing, on the second component, first information associating the first time and the second time, wherein the first information is stored in a first entry of a plurality of entries of a data structure, wherein each of the plurality of entries includes a representation of a pair of times comprising one time of the first component and a corresponding time of the second component, wherein the first entry includes a representation of the second time according to the second time standard of the second component; and
for a phenomenon involving the first component, determining, based on the first information, a third time that the phenomenon occurred according to the first time standard, wherein said determining the third time includes:
receiving an indication regarding an occurrence of the phenomenon at a fourth time according to the second time standard of the second component;
determining that the first entry, from among the plurality of entries, identifies a closest time to the fourth time; and
determining the third time of the phenomenon according to the first time standard based on the first information of the first entry.
2. The method of claim 1 , wherein the first information is stored in a directory on the second component on which phenomena that occur on the storage network, including the phenomenon, are logged.
3. The method of claim 1 , further comprising:
generating the first information between the first time and the second time, wherein the first information includes information about the first time standard and the second time standard.
4. The method of claim 3 , wherein the first time standard is for a first time zone, and the second time standard is for a second time zone, and wherein the first information includes information about the first time zone and the second time zone.
5. The method of claim 1 , wherein the first time standard has a first format, and the second time standard has a second format, the method further comprising:
generating the first information, including performing at least one of: converting the first time to another format, and converting the second time to another format.
6. The method of claim 1 , wherein sending the request, receiving the response specifying the first time, determining the second time, and storing the first information are repeated a plurality of times over a period of time to produce a plurality of information elements over the period of time, including the first information, and wherein the plurality of information elements are stored in the data structure including the plurality of entries, each entry specifying one of the plurality of information elements.
7. The method of claim 1 , wherein the first component is a storage system and the second component is a host system.
8. The method of claim 1 , wherein said determining that the first entry represents the closest time to the fourth time further comprises:
determining that the second time, from among all the corresponding times of the plurality of entries, is closest in time to the fourth time.
9. For a storage network including a first component and a second component, a system comprising:
one or more processors; and
a memory comprising code stored thereon that, when executed, performs a method comprising:
sending a request from the second component to the first component to provide a current time on the first component, wherein the first and second components are physical components in the storage network;
receiving a response to the request, the response specifying a first time when the response was sent according to a first time standard of the first component;
determining a second time when the response was received according to a second time standard of the second component;
storing, on the second component, first information associating the first time and the second time, wherein the first information is stored in a first entry of a plurality of entries of a data structure, wherein each of the plurality of entries includes a representation of a pair of times comprising one time of the first component and a corresponding time of the second component, wherein the first entry includes a representation of the second time according to the second time standard of the second component; and
for a phenomenon involving the first component, determining, based on the first information, a third time that the phenomenon occurred according to the first time standard, wherein said determining the third time includes:
receiving an indication regarding an occurrence of the phenomenon at a fourth time according to the second time standard of the second component;
determining that the first entry, from among the plurality of entries, identifies a closest time to the fourth time; and
determining the third time of the phenomenon according to the first time standard based on the first information of the first entry.
10. The system of claim 9 , wherein the first information is stored in a directory on the second component on which phenomena that occur on the storage network, including the phenomenon, are logged.
11. The system of claim 9 , wherein the method further includes:
generating the first information between the first time and the second time, wherein the first information includes information about the first time standard and the second time standard.
12. The system of claim 11 , wherein the first time standard is for a first time zone, and the second time standard is for a second time zone, and wherein the first information includes information about the first time zone and the second time zone.
13. The system of claim 9 , wherein sending the request, receiving the response specifying the first time, determining the second time, and storing the first information are repeated a plurality of times over a period of time to produce a plurality of information elements over the period of time, including the first information, and wherein the plurality of information elements are stored in the data structure including the plurality of entries, each entry specifying one of the plurality of information elements.
14. For a storage network including a first component and a second component, one or more non-transitory computer-readable media having software stored thereon comprising:
executable code that controls sending a request from the second component to the first component to provide a current time on the first component, wherein the first and second components are physical components in the storage network;
executable code that controls receiving a response to the request, the response specifying a first time when the response was sent according to a first time standard of the first component;
executable code that controls determining a second time when the response was received according to a second time standard of the second component;
executable code that controls storing, on the second component, first information between the first time and the second time on the second component, wherein the first information is stored in a first entry of a plurality of entries of a data structure, wherein each of the plurality of entries includes a representation of a pair of times comprising one time of the first component and a corresponding time of the second component, wherein the first entry includes a representation of the second time according to the second time standard of the second component; and
executable code that, for a phenomenon corresponding to the first component, controls determining a third time of the phenomenon according to the first time standard based on the first information between the first time and the second time, wherein said determining the third time includes:
receiving an indication regarding an occurrence of the phenomenon at a fourth time according to the second time standard of the second component;
determining that the first entry, from among the plurality of entries, identifies a closest time to the fourth time; and
determining the third time of the phenomenon according to the first time standard based on the first information of the first entry.
15. The non-transitory one or more computer-readable media of claim 14 , wherein the first information is stored in a directory on the second component on which phenomena that occur on the storage network, including the phenomenon, are logged.
16. The non-transitory one or more computer-readable media of claim 14 , further comprising:
executable code that controls generating the first information between the first time and the second time, wherein the first information includes information about the first time standard and the second time standard.
17. The non-transitory one or more computer-readable media of claim 16 , wherein the first time standard is for a first time zone, and the second time standard is for a second time zone, and wherein the first information includes information about the first time zone and the second time zone.
18. The non-transitory one or more computer-readable media of claim 14 , wherein sending the request, receiving the response specifying the first time, determining the second time, and storing the first information are repeated a plurality of times over a period of time to produce a plurality of information elements over the period of time, including the first information, and wherein the plurality of information elements are stored in the data structure including the plurality of entries, each entry specifying one of the plurality of information elements.