Dynamic page generator

Abstract: An custom page server is provided with user preferences organized into templates stored in compact data structures and the live data used to fill the templates stored local to the page server which is handing user requests for custom pages. One process is executed on the page server for every request. The process is provided a user template for the user making the request, where the user template is either generated from user preferences or retrieved from a cache of recently used user templates. Each user process is provided access to a large region of shared memory which contains all of the live data needed to fill any user template. Typically, the pages served are news pages, giving the user a custom selection of stock quotes, news headlines, sports scores, weather, and the like. With the live data stored in a local, shared memory, any custom page can be built within the page server, eliminating the need to make requests from other servers for portions of the live data. While the shared memory might include RAM (random access memory) and disk storage, in many computer systems, it is faster to store all the live data in RAM.

Description: BACKGROUND OF THE INVENTION The present invention relates to the field of customized information presentation. More specifically, one embodiment of the invention provides a custom page server which can quickly serve custom pages and is scalable to handle many users simultaneously. Web servers for serving static documents ("Web pages") over the global Internet are known. While static documents are useful in many applications where the information to be presented to each requesting user is the same, some applications require customization to appeal to users. For example, in presenting news to users, custom pages present news which is more relevant to the requesting users than static pages. With static pages, a user will often have to scroll through many topics not of interest to that user to get to the information of interest. With custom pages, the information is filtered according to each user's interest. Customizing a server response based on the requestor is known, however known systems do not scale well. One method of serving custom pages is to execute a script, such as a CGI (Common Gateway Interface) script, or other program to collect the information necessary to generate the custom page. For example, if the custom page is a news page containing stock quotes, sports scores and weather, the script might poll a quote server to obtain the quotes of interest, poll a sports score server to obtain the scores of interest and poll a weather server to obtain the weather. With this information, the server generates the custom page and returns it to the user. This approach is useful where there are not many requestors and where the attendant delay is acceptable to users. While it may be the case that current users are willing to wait while pages load in their browsers, growing impatience with waiting will turn users away from such servers, especially as use increases. One approach to avoiding long waits is to transfer the custom information in non-real-time, so that the information is stored local to the user as it arrives and is presented to the user on request. A disadvantage of such a system is that the networks used by the user become clogged with data continually streaming to the user and require large amounts of local storage. Another disadvantage is that the locally stored information will become out of date as the server receives new data. From the above it is seen that an improved system for delivering custom pages is needed. Quintana Y., "Knowledge-based information filtering of financial information", Proceedings of the National Online Meeting, 13 May 1997, pages 279-285, XP002057953 discloses an information management system that indexes information on a server and creates personalized summaries of new information for individual users. The system keeps track of previously viewed information and creates a personalized summary of new information for the user based on the previously viewed information. The personalized summaries may then be emailed or stored on a WWW server for the user. The information is stored on a WWW server. EP-A-0 749 081 discloses a client computer that initiates a connection to an information server and sends a portion of its user profile to an application server. The application server then determines what information needs to be downloaded to the client computer, collects the information, and sends the information to the client computer. The information is then loaded into the client computer's local database. The information is sent for storage in the client's local database. WO 97 17662 A discloses retrieving pages from a cache when a request is received. Chesnais, P.R. et al., "The fishwrap personalised news system", proceedings of the 2nd International Workshop on community networking integrated multimedia services in the home, 20-22 June 1995, pages 275-282, XP002074902, Princeton, N.J., USA discloses a personalized news system. That system maintains a list of interests that the user might be interested in and uses those interests to filter news for a user. The system also can generate a page for a user including the filtered news and users can specify sections of news that appear in their page. SUMMARY OF THE INVENTION The present invention provides a method of using a page server as set out in claim 1. User preferences are organized into templates stored in compact data structures and the live data used to fill the templates is stored local to the page server which is handing user requests for custom pages. One process is executed on the page server for every request. The process is provided a user template for the user making the request, where the user template is retrieved from a cache of recently used user templates. Each user process is provided access to a large region of shared memory which contains all of the live data needed to fill any user template. Typically, the pages served are news pages, giving the user a custom selection of stock quotes, news headlines, sports scores, weather, and the like. With the live data stored in a local, shared memory, any custom page can be built within the page server, eliminating the need to make requests from other servers for portions of the live data. While the shared memory might include RAM (random access memory) and disk storage, in many computer systems, it is faster to store all the live data in RAM. If the volume of requests becomes too great for one page server to handle, the system is easily scaled by adding additional page servers. Each page server maintains its own copy of the live data in its shared memory, and needs to maintain only the user templates for the requests it is handling, so no communication between page servers is needed. Examples of embodiments of the inventions herein may be realized by reference to the remaining portions of the specification and the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a client-server architecture according to one embodiment of the present invention; FIG. 2 is a schematic diagram showing how a user's custom page is generated from a user configuration, a global template and live data. FIG. 3 is an illustration of a global front page template as might be used to generate user templates. FIG. 4 is an illustration of a user template generated from the global front page template of FIG. 3 as might be used to generate a custom user page. FIG. 5 is an illustration of a user page generated using the global template of FIG. 4. FIG. 6 is an illustration of how intelligent defaults are selected. DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a client-server system 100 which is used to display custom news pages. A custom news page is displayed on a browser 102 which obtains the page from a page server 104 via Internet 106. While only one browser 102 is shown, a typical system will have many browsers connecting and disconnecting to the system. The art of client-server systems using HTTP (HyperText Transport Protocol) messaging or other protocols is well known and will not be addressed in detail here. Essentially, browser 102 makes a request for a particular page by specifying a Uniform Resource Locator ("URL") for the page. In the example shown in FIG. 1, the request is directed to the URL "http:/my.yahoo.com/". Normally, this URL is directed to the root directory of a machine named my.yahoo.com. As is the convention in Internet communications, browser 102 submits the domain portion ("my.yahoo.com") of the URL to a name server, such as name server 108, to determine an actual address for the page server 104. Name server 108 returns an IP (Internet Protocol) address to browser 102 directing it to a page server 104. Where multiple page servers 104 are used, name server 108 returns IP addresses in a round-robin fashion to distribute the load over multiple page servers. Alternatively, name server 108 might distribute the load more deterministic by tracking browser addresses and hashing the browser address to select a page server 104. It is deterministic in that any given browser always accesses the same page server 104. This allows for more efficient caching of user templates, since more cache hits are likely where a given browser always returns to one page server. When a page server receives the URL for its root directory, it interprets that as a request for the user's custom summary page. The user is determined not from the URL, but from a "cookie" provided by browser 102 with the URL. Cookies are strings of data stored by browsers and sent along with any request to a URL having a domain associated with the cookie. Page servers 104 obtain the live data from many disparate sources and reformat the data into a form suitable for use by the page server. Page servers 104 are coupled, via a network, to edit servers 112, which are used when a user changes his or her user template. The user templates are stored in a user configuration database 116 and are stored and provided to edit servers by a network appliance 114 written for this purpose. Network appliance 114 is a process tuned to quickly locate files in large directories (N400 files/directory) and return them to the edit servers or page servers. One embodiment of network appliance 114 is the F330 fault-tolerant scalable server supplied by Network Appliance, of Mountain View, California. In a specific embodiment, page servers 104 are microcomputers running the Unix® operating system with 64 to 128 megabytes of shared memory, page servers 104 and edit servers 112 are coupled using TCP/IP (Transport Control Protocol/Internet Protocol) and the user configuration database 116 is a Unix file structure which stores each user configuration in a text file. The particular file used by a user is a combination of the user's user name and a hash result, to allow for quick access when many user configurations are stored. For example, the user configuration for summary "front" page for a user "ash802" might be stored at /de/13/y.ash802, where "de" and "13" are hash results of a hash of the user name "ash802". FIG. 2 shows in more detail the generation of a custom page for a user, using a front page generator 200 and page server 104. Front page generator 200 generates a user template 202 from a global front page template 204 and a user configuration record 206. FIG. 3 shows an example of a global front page template. User configuration record 206 is a record selected from user configuration database 116. The record might have been obtained from a cache, but in the preferred embodiment, the records are not cached, the user templates are. Page server 104 is shown comprising a page generator 210, a shared memory 212 for storing live data and a cache 214 for caching user templates such as user template 202. Page generator 210 generates a custom front page 218 from a user template and the live data stored in shared memory 212. Although not shown, custom pages other than the front page can be generated in a similar fashion. Using user templates and a shared memory for the live data, page server 104 can quickly build custom pages in response to a user request. Where the user template is cached, the page can be generated entirely within page server 104. Shared memory 212 is organized as a set of memory mapped files. With memory mapped files, the operating system maintains the data in permanent storage, but permanently caches the files in shared memory 212. This allows for quick recovery should a page server crash, since all of the shared memory can simply be reloaded from the permanent storage. This is a great feature from a user convenience standpoint, since the user will never be faced with a situation where they have to wait for a server to rebuild a page for them by querying the various data providing servers, such as sports server 230, stock server 232 and news server 234. As should be apparent from this description and FIG. 2, page generator 210 can generate custom front page 218 much more quickly using shared memory 212 as compared with using servers 230, 232, 234 and page template 202. One reason for this is that the time it takes to retrieve data from shared memory 212 does not appreciably increase relative to the bandwidth delay time when more data is retrieved. For example, if stock server 232 were queried for each individual stock quote, a page with fifty stock quotes might take ten times as long to generate as a page with five stock quotes. One aspect of the present invention is the realization that every piece of information a person can request on a page is storable in a shared memory closely coupled to a page generator. For example, page server 104 shown in FIG. 2 can accommodate 65,000 different symbols for which quotes are provided. In one embodiment, all of the stock information for all 65,000 symbols is stored in a 13 to 14 megabytes section of the shared memory. Where shared memory 212 is a 64MB or 128MB memory, this leaves sufficient room for other data, such as news headlines, sport scores, and memory used by the operating system for each process running on page server 104. In some embodiments, shared memory 212 is large enough to also accommodate more than just news headlines. For example, news summaries (as described further in connection with FIG. 5) can be stored in shared memory 212 for quick access. As shown in FIG. 2, the user's front page template 202 does not need to be generated each time, but rather is stored in cache 214. In a preferred embodiment, user templates are stored in cache 214 for long enough to be reused. Some users might choose to access their front page only infrequently, while others might choose to access their front page hourly. Since the pages are customized and dynamic, the user would see different information each time, but the same user template would be used each time. Of course, when the user edits his or her template, any cached copy of a user template is flushed. A garbage-collection process may also flush the cache of user pages which have been inactive for several days. In one implementation, cache 214 would accommodate 60,000 to 70,000 user templates. Where a particular page server is assigned on a random round robin basis, multiple page servers may cache their own copy of a given user template, but where a user is directed always to a particular server (except in the case where the particular server fails and a secondary server is used), that page server will be the only one which needs to cache that users user template. Even where the round robin name server scheme is used, some browsers may cache IP addresses, even longer than the specified "time to live" variable associated with the IP address, in order to save the time required to obtain an IP address each time. With such a browser, the user is effectively directed to the same page server each time and the server side of the page serving system does not need to direct users to particular page servers. With newer browsers, however, the "time to live" variable is honored and new requests are made for IP addresses after the "time to live" has expired. In these cases, if the assignment of a user to a single page server is desired, name server 108 (see FIG. 1) will use the user name from the provided cookie or the user's IP address to assign a page server based on a hash of the user name or IP address. FIG. 3 is an illustration of global user template 204. Global user template 204 is an HTML (HyperText Markup Language) document with additional tags as placeholders for live data. Several placeholders 302 are shown in FIG. 3. FIG. 4 is an illustration of user template 202 as might be generated from global user template 204 (see Fig. 3) and a user configuration record 206. User template 202 is determined by the user configuration and is independent of the live data, therefore it can be cached without needing to be updated, unless the user chooses to edit the configuration information. The user templates are cached rather than the user configuration, to save a step and reduce the time to respond to a request for the page. Caching is more effective where the typical user makes several requests in a short time span and then doesn't make any requests for a long period of time. Essentially, user template 202 contains the information about the user which does not change until the user changes his or her preferences. Of course, the system operator could choose to make changes to how the system operates, thus requiring changes to the user preferences and user templates. User template 202 is shown comprising internal variables such as a time zone and demographic information. The demographic information, on the second line in FIG. 4 is used for selection of an advertisement which will be part of the custom page. In this example, the advertisement is targeted by the demographic information in the user template ":M,85,95035,T,*" indicating that a suitable ad should be targeted to a male user, age 85, located in zip code 95035, etc. As shown, the portfolio section contains selected stock symbols, the scoreboard section contains selected team symbols, and the weather section contains selected weather cities/zip codes. The selections of stock quote symbols, team scores, and weather cities are set by the user. In a preferred embodiment, intelligent defaults are selected by the system prior to user selection, so that users unfamiliar with the customization process will nonetheless be able to view non empty custom pages. This is described in further detail below in connection with FIG. 6. FIG. 5 is an illustration of a user front page 218 returned by page server 104. User front page 218 as shown in FIG. 5 includes many elements, some of which are described here in further detail. User front page 218 is built according to a user template and live data. The user template specifies, for example which quotes are shown in the portfolio module, which cities are displayed in the weather module, etc. Each of the modules 504 can be customized by a user and moved about front page 218. The modules 504 are also reusable, in that any customized module which appears on multiple pages can be edited from any one of those pages and the edits will be reflected on each of the pages. Other custom pages for the user can be viewed by selecting one of the page buttons 502 appearing below the header. Other pages and utilities can be selected using the buttons 508 which are part of the header. In addition to all of the live date shown in FIG. 5 being stored in the shared memory, summaries from each of the major news topics can also be stored in the shared memory and viewed by pressing on the news topic header, such as news topic header 506. As should be noted, the page generator can also intelligently display dates 510 customized for a particular user, using a time zone variable in the user template. This time zone variable is shown as the first line in user template 202 in FIG. 4. In addition to being able to modify each of the modules, in many cases the order of appearance of the modules is customizable. For example, the order of the various sections of user template 202 shown in FIG. 4 is not fixed. The preference editing process can be initiated by the user pressing the appropriate edit button 512. As explained above, once the editing process is complete, the user template is flushed from the cache and regenerated. Since each of the news stories is essentially a static page linked to a headline shown in the news section, these can simply be linked to static pages on a news server. Referring now to FIG. 6, an illustration of intelligent defaulting for populating a user template, and consequently a user summary page. As part of a registration process, a user indicates, among other things, his or her zip code. This zip code is used to locate an approximate longitude and latitude for the user using a zip code lookup table 602. This allows the user's location to be located on a map 604. Map 604 provides city boundaries and, with team location table 606, also provides locations for various sports teams which can be selected in a sports module. In selecting a default predetermined number of cities and sports teams for inclusion as initial selections for a particular user, a circle is drawn around the user and increased in diameter until the circle envelopes a suitable predetermined number of cities and sports teams. In this way, each user is guaranteed a default number of nearby teams and cities for sports and weather, respectively. While this assumes that the user is interested in only the teams nearest the user, the system can be arranged to provide intelligent defaults where geographic anomalies are known to exist. Geographic anomalies occur in communities which have more loyalty to distant teams than nearby teams, such as might occur when the distant team is much better than the nearby team or when the nearby team recently moved to a distant location. In any case, the user is allowed customize his or her pages beginning with the intelligent defaults selected. Other intelligent defaults can be provided in other contexts. For example, the header of user front page 218 includes a button 508 labelled "myweb" which, when pressed, would lead the user to a custom listing of web sites. The initial defaults for that custom listing of web sites might be generated based on the keywords of interest to that user or based on the news topics, sports teams or weather cities selected by the user.

Claims: A method of using a page server (104) to provide quick responses to user requests from a plurality of users for customized pages, the method comprising the steps of: obtaining user preferences for the plurality of users, wherein a user's user preferences indicate items of interest to that user; obtaining live information from information sources; storing the live information in a storage device; characterised in that the method further comprises the steps of: for each of the plurality of users, combining the user preferences for a specific user and a template (204) to form a template specific to the user (202) at the page server (104); storing the template specific to the user (202) in a cache (214); receiving, from a user and at the server (104), a user request for a customized page (218) customized according to the user preferences; generating the customized page at the page server (104) using the template specific to the user and using the live information stored in the storage device as input to the template; and providing the user with the customized page, wherein the steps of generating and providing are performed in quick response to receipt of the user request in the step of receiving and wherein the customized page (218) includes at least one item of live information selected from the storage device. The method of claim 1, wherein the live information comprises stock quotes, sports scores and news headlines. The method of claim 1, wherein the step of storing the live information in a storage device is a step of storing the live information in a memory having a capacity to simultaneously contain all of the live information that is required for generating the customised page. The method of claim 1, wherein the server (104) simultaneously handles more than one thousand user requests by assigning user requests to one of the plurality of servers. The method of claim 1, further comprising a step of caching templates for users for whom user requests have been recently serviced. The method of claim 1, further comprising a step of generating a default user configuration for a user based on demographic information of that user. The method of claim 6, wherein the step of generating a default user configuration comprises the steps of: determining a default list of cities for a weather report based on user demographic information; and determining one or more sports teams for sports reporting based on user demographic information. The method of claim 7, wherein the steps of determining comprise the steps of: obtaining user postal code information; translating the postal code information to user geographic position; comparing the user geographic position to geographic positions assigned to each city and sports team; and determining a threshold distance from the user geographic position which is greater than or equal to a distance to a predetermined nonzero number of cities and a predetermined nonzero number of sports team geographic positions.

Inventors: NAZEM FARZAD, PATEL ASHVINKUMAR P, NAZEM, FARZAD, PATEL, ASHVINKUMAR P.
Applicants: YAHOO INC, YAHOO, INC.
Application year: 1998
Main classification: G06F17
IPC codes: G06F17