The configuration in which the base of the transistor is common between emitter and collector circuit is called a common base configuration. In common base-emitter connection, the input is connected between emitter and base while the output is taken across collector and base. In the common base configuration, the collector current IC is the output current, and the emitter current IE is the input current. Thus, the ratio of change in emitter current to the collector at constant collector-base voltage is known as a current amplification factor of a transistor in common base configuration.
If the user or operating system erases a file not just remove parts of itthe file will typically be marked for deletion, but the actual contents on the disk are never actually erased.
This reduces the LBAs needing to be moved during garbage collection. The result is the SSD will have more free space enabling lower write amplification and higher performance.
The benefit would be realized only after each run of that utility by the user.
The user could set up that utility to run periodically in the background as an automatically scheduled task. It will take a number of passes of write amplification factor and voltage data and garbage collecting before those spaces are consolidated to show improved performance.
The portion of the user capacity which is free from user data either already TRIMed or never written in the first place will look the same as over-provisioning space until the user saves new data to the SSD.
If the user saves data consuming only half of the total user capacity of the drive, the other half of the user capacity will look like additional over-provisioning as long as the TRIM command is supported in the system. With an SSD without integrated encryption, this command will put the drive back to its original out-of-box state.
This will initially restore its performance to the highest possible level and the best lowest number possible write amplification, but as soon as the drive starts garbage collecting again the performance and write amplification will start returning to the former levels.
One free tool that is commonly referenced in the industry is called HDDerase. They simply zeroize and generate a new random encryption key each time a secure erase is done. In this way the old data cannot be read anymore, as it cannot be decrypted.
Wear leveling If a particular block was programmed and erased repeatedly without writing to any other blocks, that block would wear out before all the other blocks — thereby prematurely ending the life of the SSD.
For this reason, SSD controllers use a technique called wear leveling to distribute writes as evenly as possible across all the flash blocks in the SSD. In a perfect scenario, this would enable every block to be written to its maximum life so they all fail at the same time.
Unfortunately, the process to evenly distribute writes requires data previously written and not changing cold data to be moved, so that data which are changing more frequently hot data can be written into those blocks. Each time data are relocated without being changed by the host system, this increases the write amplification and thus reduces the life of the flash memory.
The key is to find an optimum algorithm which maximizes them both. The process requires the SSD controller to separate the LBAs with data which is constantly changing and requiring rewriting dynamic data from the LBAs with data which rarely changes and does not require any rewrites static data.
If the data is mixed in the same blocks, as with almost all systems today, any rewrites will require the SSD controller to garbage collect both the dynamic data which caused the rewrite initially and static data which did not require any rewrite.
Any garbage collection of data that would not have otherwise required moving will increase write amplification. Therefore, separating the data will enable static data to stay at rest and if it never gets rewritten it will have the lowest possible write amplification for that data.TRANSISTORS AND AMPLIFICATION.
If a voltage is applied to the junction as shown in Figure 1a) appears as a multiplicative factor in the expression for this resistance. You can also calculate I C: I C = bI B ~ V B /R E.
Eqn.(8) The collector voltage V C is obviously given by. The voltage and current relations in the triode for both anode and grid are of importance along with figures like triode amplification factor, the anode or plate resistance and the transconductance.
All of these give an understanding of the performance of a particular triode vale or triode vacuum tube.
The amplification factor, also called gain, is the extent to which a device boosts the strength of a signal. The damping factor, also called loss, is the extent to which a device reduces the strength of a signal.
The common form factor chosen was the 15mm ” U.2 form factor. The common interface was the NVMe protocol over a PCIe interface. Designing for a common form factor created new challenges. Write amplification factors Factor Description Type Relationship* Garbage collection: The efficiency of the algorithm used to pick the next best block to erase and rewrite.
Write Amplification Factor and Data Workloads Flash memory is rarely perfectly utilized, and there is usually some inefficiency resulting in an acceleration of drive wear. The Write Amplification Factor (WAF) is a representation of how effectively the flash is used where the higher the WAF, the lower the efficiency.