Jimmy Tran
Dabbler
- Joined
- Dec 27, 2015
- Messages
- 33
Hi All, I'm a noob to FreeNAS but have done quite a bit of research already. I just need some final recommendations on which way to go. I look forward to everyone's responses.
Setup:
SSG-6028R-E1CR12L Chassis
E5-2630V3 2.4 GHz
4 x 16GB DDR4 ECC REG DIMM
8 x WD 4TB RE Drives: Pool currently has 2 striped vdevs NO Compression
3 x Dell PE R610 X5550 8 x 2.659GHz
10Gbe Storage Network
1. I like VAAI and it looks like iSCSI is the only way to get it. Is there really any other benefit going with iSCSI as I don't have any apps that require block level access? I just would like the cloning and migrations to be quick but maybe that isn't necessary with a 10Gb network?
2. When testing with NFS, I was getting terrible speeds. After much reading (wish I did it first before testing) it looks like I need a SLOG due to the write sync. Is there a better option than the Intel SSD s3700 in a RAID 1?
3. Write Cache: My write cache would allow up to 8GB per transaction group. (64GB x 1/8). The pool has 8 disks capable of writing at 150MB/s. Would be Transaction Group be 6GB based on the info below?
150MB/s x 8 = 1200MB/s
6GB transaction group size (5 seconds)
If my calculations are correct, my write cache in RAM is more than my disks can handle. Does that mean ZFS will stop and wait for my flush to disk to finish? I'm a little confused about the IO stopping and waiting...
What if I have two separate vdevs with 4 disks each. Would the calculations above still be the same?
4. SLOG Size: Should the SLOG partition be 32GB since that is half of my available RAM or should it be equivalent to two times my Transaction Group size? I'm getting some mixed info...
5. iSCSI zvol: I was reading it should be more than 1TB and less than 50% full for optimum performance. Is there such a requirement for NFS?
I think those are all of my immediate concerns to get things going. Appreciate the responses and guidance!
Setup:
SSG-6028R-E1CR12L Chassis
E5-2630V3 2.4 GHz
4 x 16GB DDR4 ECC REG DIMM
8 x WD 4TB RE Drives: Pool currently has 2 striped vdevs NO Compression
3 x Dell PE R610 X5550 8 x 2.659GHz
10Gbe Storage Network
1. I like VAAI and it looks like iSCSI is the only way to get it. Is there really any other benefit going with iSCSI as I don't have any apps that require block level access? I just would like the cloning and migrations to be quick but maybe that isn't necessary with a 10Gb network?
2. When testing with NFS, I was getting terrible speeds. After much reading (wish I did it first before testing) it looks like I need a SLOG due to the write sync. Is there a better option than the Intel SSD s3700 in a RAID 1?
3. Write Cache: My write cache would allow up to 8GB per transaction group. (64GB x 1/8). The pool has 8 disks capable of writing at 150MB/s. Would be Transaction Group be 6GB based on the info below?
150MB/s x 8 = 1200MB/s
6GB transaction group size (5 seconds)
If my calculations are correct, my write cache in RAM is more than my disks can handle. Does that mean ZFS will stop and wait for my flush to disk to finish? I'm a little confused about the IO stopping and waiting...
What if I have two separate vdevs with 4 disks each. Would the calculations above still be the same?
4. SLOG Size: Should the SLOG partition be 32GB since that is half of my available RAM or should it be equivalent to two times my Transaction Group size? I'm getting some mixed info...
5. iSCSI zvol: I was reading it should be more than 1TB and less than 50% full for optimum performance. Is there such a requirement for NFS?
I think those are all of my immediate concerns to get things going. Appreciate the responses and guidance!