Calculating the optimal number of LBNS to prefetch per CPU
The present disclosure generally relates to prefetching data from one or more CPUs prior to the data being requested by a host device. The prefetched data is prefetched from memory and stored in cache. If a host device requests data that is not already in cache, then a determination is made regarding whether the data is scheduled to be written into cache. If the data is not in cache and is not scheduled to be written into cache, then the data is retrieved from memory and delivered to the host device. If the data is scheduled to be written into cache, or is currently being written into cache, then the request to retrieve the data is delayed or scheduled to retrieve the data once the data is in cache. If the data is already in cache, the data is delivered to the host device.
1. A method, comprising:
receiving a first request from a host device to read a first data and a second request to read a second data from a memory device that is coupled to a plurality of CPUs, wherein a first CPU of the plurality of CPUs has a first cache storage and a second CPU of the plurality of CPUs has a second cache storage;
reading the first data from the memory device using the first CPU;
reading the second data from the memory device using the second CPU of the plurality of CPUs;
writing the first data and the second data to the first cache storage of the first CPU;
reading the first and second data from the first cache storage; and
delivering the first and second data to the host device.
2. The method of claim 1 , wherein the memory device is a NAND storage device.
3. The method of claim 1 , wherein the memory device is a hard disk drive storage device.
4. A method, comprising:
receiving a first request from a host device to read a first LBA data from a a first LBN and a second LBN disposed in a memory device that is coupled to a first CPU and a second CPU, wherein the first CPU has a first cache storage and is assigned the first LBN, wherein the second CPU has a second cache storage and is assigned the second LBN;
reading a first portion of the first LBA data from the first LBN of the memory device;
reading a second portion of the first LBA data from the second LBN of the memory device;
writing the first portion of the first LBN data and the second portion of the first LBN data to the first cache storage;
reading the first LBA data from the first cache storage; and
delivering the first LBA data to the host device.
5. The method of claim 4 , further comprising:
receiving a second request from the host device to read a second LBA data from the memory device, wherein the first LBA data and the second LBA data are sequential data;
reading the second LBA data from the memory device;
writing the second LBA data to the first cache storage; and
delivering the second LBA data to the host device.
6. The method of claim 5 , wherein the writing the second LBA data to the first cache storage occurs prior to receiving the second request.
7. The method of claim 4 , wherein the reading the first portion of the first LBA data is performed by the first CPU and reading the second portion of the first LBA data is performed by the second CPU.