I've been wading through tons of threads trying to piece together info on configuring a SSD for SLOG so I can maximize write endurance, but haven't been able to find any clear definitive guide on the topic. In fact, there even seems to be conflicting info on how best to do this. Please note I'm NOT asking which Brand/Model/NAND Technology has the highest write cycles, but more about "maximizing" the writes so it creates even wear on the SSD and thus increasing total writes I can perform on the drive, regardless of the drive's Max. write cycles. Can someone please help me with these questions?
1. Most posts claim "modern SSDs" have some sort of intelligent write leveling across the drive. If so, why do we still need to underprovision/overprovision, especially if SLOG will most likely not exceed 6.25GB even on a fast 10Gbe network? If I have a 120GB SSD, that's plenty of space for the controller to take care of write leveling across unused space, no? Why wouldn't I just leave it as one big partition?
2. Underprovisioning vs Overprovisioning? Is this just a semantics thing or is there a difference? If so, which method is better for write cycles?
3. Some posts claim SSD controllers will only distribute writes across free space WITHIN a partition, while some say it will distribute writes across ALL unused space, including space outside the partition. Which one is it or does it depend on SSD vendor? If it's the former, then wouldn't underprovisioning actually shorten the life of the drive since a 8GB underprovioned partition would constantly be written over?
I apologize if all this info is already out there, but the forum has gotten to a size that makes reading through every old thread a full day task. If the topic is already covered, can someone please provide a link?
Thanks
1. Most posts claim "modern SSDs" have some sort of intelligent write leveling across the drive. If so, why do we still need to underprovision/overprovision, especially if SLOG will most likely not exceed 6.25GB even on a fast 10Gbe network? If I have a 120GB SSD, that's plenty of space for the controller to take care of write leveling across unused space, no? Why wouldn't I just leave it as one big partition?
2. Underprovisioning vs Overprovisioning? Is this just a semantics thing or is there a difference? If so, which method is better for write cycles?
3. Some posts claim SSD controllers will only distribute writes across free space WITHIN a partition, while some say it will distribute writes across ALL unused space, including space outside the partition. Which one is it or does it depend on SSD vendor? If it's the former, then wouldn't underprovisioning actually shorten the life of the drive since a 8GB underprovioned partition would constantly be written over?
I apologize if all this info is already out there, but the forum has gotten to a size that makes reading through every old thread a full day task. If the topic is already covered, can someone please provide a link?
Thanks