Hello everybody,
i have a strange behaviour in my test environment and appreciate every kind of tip!
TrueNAS is installed on a Proxmox hypervisor - the VM has 8 GB of RAM, 4 CPUs and a "normal" HDD and a 40 GB SSD passed throug from the proxmox host.
I set up one pool for each disk which is provided as iSCSI volume to the proxmox machine.
The goal of this scenario is to benchmark the performance of the VM-provided storage compared to the same storage via iSCSI.
Testing with fio, i get the strange behaviour that the storage accessed via iSCSI seems to be faster (~18 MB/s) than the fio test from the TrueNAS VM itself (~283 kb/s).
The tests are running with sync=always and the following fio command:
fio --name=random-write --rw=randwrite --bs=4k --size=4g --numjobs=1 --iodepth=1 --runtime=60 --time_based --end_fsync=1
ZFS Deduplication is off, atime is off, compression is set to LZ4. The other options are set to TrueNAS defaults. The Network between the VM and its host is 10 G via virtio driver. The CPU of the VM is set to qemu64.
Normally, testing with a block size of 4k should result in a poor throughput perfomance, but i expected it the other way round because of the latency of the iSCSI connection.
Could somebody help me, finding my fault? Something in here is very weird...
- Is fio under FreeBSD acting in an other way than under Linux?
- Are there probably any buffers which affect the results?
- Am I using wrong parameters in the fio test command?
Any help is appreciated - I hope I didn't forget any important information...
Thanks in advance!
i have a strange behaviour in my test environment and appreciate every kind of tip!
TrueNAS is installed on a Proxmox hypervisor - the VM has 8 GB of RAM, 4 CPUs and a "normal" HDD and a 40 GB SSD passed throug from the proxmox host.
I set up one pool for each disk which is provided as iSCSI volume to the proxmox machine.
The goal of this scenario is to benchmark the performance of the VM-provided storage compared to the same storage via iSCSI.
Testing with fio, i get the strange behaviour that the storage accessed via iSCSI seems to be faster (~18 MB/s) than the fio test from the TrueNAS VM itself (~283 kb/s).
The tests are running with sync=always and the following fio command:
fio --name=random-write --rw=randwrite --bs=4k --size=4g --numjobs=1 --iodepth=1 --runtime=60 --time_based --end_fsync=1
ZFS Deduplication is off, atime is off, compression is set to LZ4. The other options are set to TrueNAS defaults. The Network between the VM and its host is 10 G via virtio driver. The CPU of the VM is set to qemu64.
Normally, testing with a block size of 4k should result in a poor throughput perfomance, but i expected it the other way round because of the latency of the iSCSI connection.
Could somebody help me, finding my fault? Something in here is very weird...
- Is fio under FreeBSD acting in an other way than under Linux?
- Are there probably any buffers which affect the results?
- Am I using wrong parameters in the fio test command?
Any help is appreciated - I hope I didn't forget any important information...
Thanks in advance!