Romex Software Forum

If PrimoCache creates an MBR partition for a cache, then that's where's the 2TB limit from - MBR partitions can't be bigger than 2TB (their size, in sectors which are 512 bytes big, are stored in 32bits). Anyway, at that many GBs of RAM index alone, I would start to worry about memory bandwidth... ...

@Axel Mertes, The major factor is the block size. Bigger the block size, smaller overhead. See FAQ . Also currently supported maximum L2 cache size is about 2TB (2044GB). And we will overcome this limit in future. Thanks. Hi Support! Above you mention the current limit is 2 TB of L2 SSD cache. Give...

Hi Support, I analyzed the values you presented for the overhead and was a bit confused about some findings. For some reasons you need more memory per block, the less blocks are indexed in total. Does that make any sense? See the yellow marked fields in the attached table for details. They show how ...

rutra80 wrote:exFAT supports cluster sizes up to 32MB

Good to know. I am just not sure yet how safe exFAT is compared to NTSF or the newer ReFS. With huge amounts of data that's important for me.

Thanks,
Axel

Well, this block size means the cache block size which can be set in the cache configuration. It does not refer to the file system's cluster size. You don't need to format the drive, just change the cache configuration. Does it really make sense to use a different block size for the cache than for ...

Hi Support, many thanks for that overview - very very helpful! You mention 512 KByte block size. Is there an option in Windows to format drives using that block size? If I remember correctly, there is only the option to format with 64 KByte maximum. If there is trick I'd like to know it. Best regard...

Hi Support! Thanks for chiming in into this discussion. I agree with the block size being important. When I am able to re-format the drive to be cached, I'll choose the biggest possible block size. Thats apparently 64 KBytes per block as of now. You say the maxium L2 cache supported is 2 TByte. So h...

Hi Slavius, thanks for the comments, very helpful summary. I still would love to see someone from Romexsoftware explaining how to calculate the size of RAM required to index an SSD cache. Here is the point: With Windows Server 2012 I can create a so called storage space, consisting e.g. of a HDD arr...

I am facing a similar issue. I dumped one large partitions directory/file structure to a log file and wrote a small program to analyze that. I've checked for file sizes matching any power of 2 block size, like 1, 2, 4, 8, 32, 64, 512, 1K, 2K, 4K, 8K, 16K, 32K, 64K, 128K, 256K, 512K. I notice the tot...

My math was not about holding an index for every source block BUT for every SSD cache block. The amount of RAM needed to index only the SSD cache blocks is larger than my physical RAM, so this is why I came to this conclusion. OK, they might read enough source blocks in a row to fill the cache and g...