Can't get writing caching to work. Topic is solved

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Myg
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Can't get writing caching to work.

Post by Myg »

Hello,
I just bought the program after testing it for a couple days. During my testing I had used Crystaldiskmark to benchmark my L1 (32GB) cached SSD (WD Blue SN550 NVMe SSD) and I had seen numbers of read up to 12GB/s which is amazing but my writing was not effected at all by the caching; it stayed around 1.5GB/s no matter what setting I used, which is basically it's default speed. I assumed the writing limit was a trial one but I found the purchased product acts the same way. Am I doing something wrong or is the program broken for this specific SSD? Any help would be appreciated.

Thanks
janusz521
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Re: Can't get writing caching to work.

Post by janusz521 »

You do not mention if you have Defer-Write enabled. It is essential to see disk write speed up. Otherwise, the data goes directly to the drive.
Myg
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Re: Can't get writing caching to work.

Post by Myg »

I did not think I had to enable to get the basic functionality working. Based on what I have seen it isn't necessary to achieve the caching ability. Can I get an official answer from support?
Mecky
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Re: Can't get writing caching to work.

Post by Mecky »

Why not? It makes sense, as write caching with RAM is putting your data integrity at risk in case of a power failure... So making it default wouldn't be "good"
Myg
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Re: Can't get writing caching to work.

Post by Myg »

Well that makes sense mecky but why does it give the ability to set Read and Write percentage without enabling the "Enable Defer-Write" setting? Why are those two seperate?
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Support
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Re: Can't get writing caching to work.

Post by Support »

To improve the write performance, you have to enable the "Defer-Write". Otherwise, write-data goes directly to drives.
The setting of Read/Write cache space is to determine how much space is used for caching read-data or write-data. If you cache write-data, but without "Defer-Write" enabled, these data will go to the cache as well as the drive. Later, if you read these data, they can be directly read from the cache, without the need of reading from the drive again. So even you have not "Defer-write" enabled, this is also a tunable setting for read cache performance. Of course, if you have "Defer-Write" enabled, you also need to set write cache space or share read/write space.

Also see Q10 in the FAQs: https://www.romexsoftware.com/en-us/pri ... e/faq.html
Myg
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Re: Can't get writing caching to work.

Post by Myg »

Thanks.
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