logo
Tags down

shadow

Page Fault - How does os search for the page in secondary storage?


By : ArrCee
Date : October 16 2020, 08:10 AM
like below fixes the issue
My question is when a page fault occurs and the required page is not in RAM ,after that how does the os know where to look for the given page in the entire secondary memory to bring it to the RAM?
code :


Share : facebook icon twitter icon

First Step in Understanding Paged Virtual Memory: Creating Page Table Entry upon Initial Page Fault


By : Sites94
Date : March 29 2020, 07:55 AM
seems to work fine The only real issue I can see with it is that search_tbl()'s return type is tbl_entry* but it is actually returning a tbl_entry. That could be a major issue though, thinking about, it if the page table is really an array of pointers to page table entries. Also, if sizeof(tbl_entry) > sizeof(tbl_entry*) you are not allocating enough space for the table.
Another issue might be getbits(). It's normal practice to number the bits of an n-bit integer type with 0 as the least significant bit and n - 1 as the most significant bit. If that is the case for the getbits() API, you are calculating the index based on the wrong part of the address.
code :
uint32_t getbits(uint32_t x, unsigned int p, unsigned int n)
{
    return (x >> (p + 1-n)) & ~(~0 << n);
}
vfn = getbits(x, 31, 20); // 31 is the top bit, number of bits is 32 - log2(4096)

Free a physiclal memory page and force a page fault


By : Ramana
Date : March 29 2020, 07:55 AM
it fixes the issue After looking into this for a while seems like try_to_unmap is the function I am looking for.

If a page's pte is marked with _PAGE_USER bit to 0, does it result in page fault or general_protection exception?


By : Mahesh Chowdary Chim
Date : March 29 2020, 07:55 AM
I hope this helps .
But who maps the user/supervisor mode bit to the privilege level, is it the MMU or the CPU?

When a page fault is returned from disk to physical memory, where is the page placed?


By : MysticUser
Date : March 29 2020, 07:55 AM
it fixes the issue You have a bit of confusion. Processes only see LOGICAL ADDRESSES. Logical addresses are mapped to PHYSICAL ADDRESSES using PAGE TABLES.
A page fault occurs when a process accesses a logical address that does not have a mapping to a physical address.

Can a page fault be generated due to the absence of the page of inner page table?


By : Adr
Date : October 14 2020, 01:00 AM
I hope this helps . In forward mapped page tables [ x86, arm ], yes faults will be generated if a page table walk encounters a missing page table. You typically need the top most (most significant bits ) table, but any of the intermediate ones can be missing.
Related Posts Related Posts :
  • Is there such a thing as a filename that is too long?
  • Karate - [#document: null] in output
  • SAP Introspection: Resolve ForeignKey
  • Flask: Trouble resolving endpoint locations in package
  • Metadata in DynamoDB stream event for delete operation?
  • Create waf size feature
  • Floating decimal point type in Haxe
  • Installing Spyder (updated for 2018)
  • How to use Active Directory Authentication in ASP.NET Core?
  • ABAP: from get_auth_values() result to SQL query
  • AOSP build for Samsung Galaxy Tab A
  • Allow to find only users members of a specific group in 1 query
  • How can I easily label my data in Power BI?
  • Use or not, of lambda to define a function in Racket
  • Can I use GitHub's Linguist as a replacement to Rouge in Jekyll
  • Storing streamed tweets in a list for further analysis
  • Swagger permanent authorization token
  • Output index of ELKI
  • Diverts deleted when restarting ActiveMQ Artemis
  • Sum-up and then calculate vs. calculate and then sum-up (SSAS-MDX)
  • xQuery - fill custom array
  • Issue with javax.mail and attached file
  • How to change the theme colors in Vuetify in standalone/CDN mode?
  • WildFly 10.0 port offset "9" can't connect to CLI at 9999
  • 401 Error when sending data to Stripe `Customers` API
  • When would a linked list be preferred over a circular buffer?
  • How to get Facebook page feed and Filter its fields as Json using Google App script
  • How to delete or set lifespan to zero - Dialogflow Agent Context
  • How to update Mat-Input Place Holder on Focus
  • How to show the Systray Icon and also the corresponding executable in the taskmanager by default when we run the install
  • Google Smart Home Agent responded Empty JSON
  • Using conditionalpanel in shiny where input is a vector
  • How many images are generated by keras fit_generator?
  • feed data to fitDataset()
  • Storm simple jdbc mapper write array to phoenix db not supported?
  • Unable to install the printer driver . Operation could not be completed (error 0x0000007e)
  • What is causing my ToDataSourceResult error in my KendoUI Core Application?
  • Questions abous blockchain and ethereum
  • SUMO: How to add new routing algorithm
  • Automation Anywhere. Using variables to select window in object cloning command
  • Numerical issues integrating a pulse signal that is delayed (fixedDelay)
  • JavaFX Boolean Binding and TableView Binding multiple
  • Does RavenDb's `Include` support constructing a document id, not just selecting one?
  • Extract tokens from grammar
  • How to install only test dependencies with Zef
  • Nexus Repository Manager 3.14 with Ceph blobstore performance
  • Implement custom RDF4J function for GraphDB
  • gRPC Java Client - hasNext during onNext?
  • Make InfluxDB/Grafana cumulative function that resets daily (sawtooth graph)
  • Using newer version of nodejs in a ruby project with cloud foundary
  • Downsides of using Shade plugin relocation feature
  • How to add JMS Message Header Property from WLST
  • GetDateFormatEx format string and custom text
  • File not found in Gitlab-CI
  • Using collision to pick up items
  • Polygon on Bing Map using Local GeoJSON Object results in wrong location
  • Searching for a Blame
  • Outlook Add In Recipient Not Being Returned
  • Verify the signing of manifest and application files
  • Gulp 4 watch gulp.series only run one time
  • shadow
    Privacy Policy - Terms - Contact Us © voile276.org