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My SSD:
I have a Samsung 970 EVO Plus NVMe M.2 1TB (PCIe 3.0) SSD. The SSD has a TBW of 650.
My HDD:
I have a Seagate BarraCuda 1 TB �C 3.5 Inch SATA 6 Gb/s 7200 RPM 64 MB Cache (ST1000DM010-2EP102) HDD.
Now, obviously the SSD is way faster than the HDD. But, as we all must know: the SSD has a limited write endurance, but the HDD does not have a limited read/write endurance.
I am using Linux.
My server has a MySQL database which most of the time performs INSERT and UPDATE commands, for example: 2-3 of these commands per minute, depending on the usage of the website. And all the others are SELECT commands, probably: 50 times per minute.
And, I constantly compile, and create programs in the same machine, i.e. ./configure, make, make install, rm -rf /usr/local/installedprogramfolder, and repeat the same many times a day, probably about 500 times a day.
Due to the above, I think compiling and creating programs, removing then repeating the same is not so good for the TBW of the SSD. But, The hard drive is slower than the SSD, resulting in less work done in a day, i.e. lower efficiency.
And the above ^ is where I am unable to decide if I need to use the SSD or the HDD!
Yes, this question might need answers based on opinion, but, still, I have narrowed it as much as possible.
I could go with an Enterprise SSD, but my budget is under Indian Rupees. 20,000 (about 275 USD), and the current SSD would just go to waste unless I assign a specific use to it.
About Backups:
The stuff inside the server is very confidential. Passwords and chat messages in the MySQL database. But, the stuff are encrypted. A remote backup wouldn’t be really good for privacy in terms of this I believe; I keep backups in multiple External 3 TB drives.
Other stuff:
Someone suggested me to use RAID, to combine multiple drives.
I will try that trick later, when I buy another HDD. Maybe in a few weeks. Sorry.
Surely, someday, I will have the money to keep buying these SSDs, but not today though.
Btw, now, I have understood that HDDs are also a victim of wear ?I forgot that HDDs wear down because of the spinning disc inside of it.
Answer: If you have a system with similar load profile and it already runs for some extended time under near expected load, you can have a estimate how much writes and reads it is doing, using iostat -th (from the package sysstat):
avg-cpu: ?%user ?%nice %system %iowait ?%steal ?%idle ?4,8% ?0,0% ?1,7% ?0,5% ?0,0% ?93,1% ?tps ?kB_read/s ?kB_wrtn/s ?kB_read ?kB_wrtn Device ?86,51 ?1,7M ?590,7k ?2,9T ?1014,8G sda ?3,47 ?29,5k ?734,9k ?50,6G ?1,2T sdb
and compare that with uptime value:
10:54:04 up 20 days, 20:26, ?1 user, ?load average: 2,18, 2,13, 1,94
As you can see, sda on this system reads of around 2.9T/20.8days = 140G per day, and writes of around 48G per day. This value must be compared with desired SSD’s datasheet value, TBW, to calculate how long it will endure this particular load.
I am sure your your fears are in vain. I found a cheapest SSD in our local store, it has a TBW value of 70 TB. That SSD will be able to endure that load for 1458 days or slightly less than 4 years. Note, my load is from an office hypervisor, there is some accountancy VM, file server; also we run many test labs there and more.
I mean, it’s quite hard to wear out a modern SSD, even cheapest one! It’ll likely break earlier by different reason other that expected wear out.