Forum: CAT Tools Technical Help
Topic: Using a RAM disk to make CAT tools faster
Poster: Samuel Murray
Post title: @Viesturs
[quote]Viesturs Lacis wrote:
That used to be true for "traditional" SATA-connected SSDs. High-end M.2 form factor SSDs, increasingly supported by modern motherboards, are able to work several times faster. [/quote]
Yes, sorry, the purpose of my original quote (which I now edited) was to show that RAM is much, much, much faster than SSD. To satisfy my own curiosity, I ran a quick benchmark on the three drives in my computer, and my RAM. Read and write speeds were about the same.
5200 rpm HDD: large files 120 MB/s, small files 2 MB/s
SATA3 SSD: large files 350 MB/s, small files 30 MB/s
NVMe M.2 SSD: large files 2000 MB/s, small files 50 MB/s
DDR4 3000 RAM: all files 12500 MB/s
...and I think the benchmark that is relevant for CAT tools is "small files". However, this is not the whole story (see below).
[quote]For example, the Samsung 970 Evo Plus claims peak read and write speeds of 3500 and 3300 MB/s, respectively. [/quote]
The "peak" mentioned in such claims is when copying very large files (gigabytes), and importantly: while the drive is not being used for anything else. I tested it briefly: on my M.2 SSD, when I make a copy of a 1 GB file (i.e. on the same disk, i.e. read and write simultaneously), it runs at 200 MB/s, but if I copy two 1 GB files simultaneously, both tasks run at only about 30 MB/s. On my RAM disk, making a copy of the same 1 GB file runs at 600 MB/s. However, unexpectedly, copying 5000 files of about 150 KB each runs equally fast on the SSD and the RAM disk (about 6-10 MB/s).
Topic: Using a RAM disk to make CAT tools faster
Poster: Samuel Murray
Post title: @Viesturs
[quote]Viesturs Lacis wrote:
That used to be true for "traditional" SATA-connected SSDs. High-end M.2 form factor SSDs, increasingly supported by modern motherboards, are able to work several times faster. [/quote]
Yes, sorry, the purpose of my original quote (which I now edited) was to show that RAM is much, much, much faster than SSD. To satisfy my own curiosity, I ran a quick benchmark on the three drives in my computer, and my RAM. Read and write speeds were about the same.
5200 rpm HDD: large files 120 MB/s, small files 2 MB/s
SATA3 SSD: large files 350 MB/s, small files 30 MB/s
NVMe M.2 SSD: large files 2000 MB/s, small files 50 MB/s
DDR4 3000 RAM: all files 12500 MB/s
...and I think the benchmark that is relevant for CAT tools is "small files". However, this is not the whole story (see below).
[quote]For example, the Samsung 970 Evo Plus claims peak read and write speeds of 3500 and 3300 MB/s, respectively. [/quote]
The "peak" mentioned in such claims is when copying very large files (gigabytes), and importantly: while the drive is not being used for anything else. I tested it briefly: on my M.2 SSD, when I make a copy of a 1 GB file (i.e. on the same disk, i.e. read and write simultaneously), it runs at 200 MB/s, but if I copy two 1 GB files simultaneously, both tasks run at only about 30 MB/s. On my RAM disk, making a copy of the same 1 GB file runs at 600 MB/s. However, unexpectedly, copying 5000 files of about 150 KB each runs equally fast on the SSD and the RAM disk (about 6-10 MB/s).