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As ssd benchmark12/6/2023 Now, whenever data is deleted or shuffled (and the old location is no longer valid), it takes too much time to wipe each sector as you go - performance would suck. Now, as data gets stored, free space goes down (super pro-tip, right?) but data also is constantly getting shuffled around on an SSD to spread out usage patterns and optimize endurance. Since data on an SSD doesn't need to be contiguous, it usually goes wherever it can quickly find a nice open slot. In your example, it sounds like you've written hundreds of GB to a drive and see performance degrading well below what it should. My spidey-sense is telling me that trim isn't working. Now, a cache should usually empty out in seconds, so if you're seeing hours before performance returns then something else funky is happening. (Expensive enterprise drives will have an onboard battery to protect this DRAM.)Īll of that brings us to this: we don't know what types/sizes of cache the drive you're using has. This can even be further boosted with a DRAM cache for very fast, small writes - but DRAM is volatile so if power is lost then the data is lost. This will allow hundreds of GB to be written quickly to the cache so that the OS can get back to work while the drive's internal controller moves those files to the slower TLC in the background. For example, a "gaming" SSD will use 95% TLC to boost storage ability, and 5% SLC as a write-buffer (cache). Prosumer and consumer drives will have a mix of flash types that give a balance of endurance and performance at multiple different price/performance points. These will have the best endurance and performance specs, but will also be the most costly. Adding more bits to a cell is a cost-saving technique at the expense of speed and endurance - so you're going to find a huge variety of configurations to match multiple price points and potential use cases.Įnterprise drives are going to have the largest share of SLC. Also, MLC (multi-layer, which is really two-layer), plus TLC and QLC for 3- and 4-layer. The fastest and highest endurance is SLC (single-layer cell). There are several different types of NAND flash used in SSDs. So many factors at play here, we don't have enough info. If you do want to write your own tests, these sections might help: But, if you just want results and don't care about the machinery underneath, then maybe it's something worth trying. Personally, I ended up preferring to just write my own tests. If you're not keen on digging into writing your own custom fio tests and interpreting the results, this could be a good solution as it handles a lot of the details and will auto-generate & save the charts for you. Yes, I'm familiar with the test suite, I've used it before and got adequate results. In this example, we plot the data for four different solid state drives in one chart." If that's not what you're looking for, perhaps a better description would help us help you. This data can be parsed and graphed over time. If you use the benchmark tool included with fio-plot, this data is logged every 0.5 seconds. In the first link I mentioned, there's a section that seems to be exactly what you were asking for: "Fio records a 'performance trace' of various metrics, such as IOPs and latency over time in plain-text. You can choose how long the tests should run for, and even add in a ramp time if you want to ensure any caches are saturated before the recording/countdown begins. It can output logs for bandwidth, latency, or IOPS with entries at specific time intervals. Yes dude, fio can do pretty much any benchmark you need it to.
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