first of all want to say that primocache is awesome! I were using for some month, with ram as cache and it works perfect even with the defer write.
Now That i don't have enough space I bought a 512GB NVME and I want to use it as cache for an iscsi volume running on my synology. SO I can have 4TB of space for my video stuff and the important here is the defer write for me more than the reading cache.
I configured the ISCSI and the read caching works perfect I got like 1GB/s of speed reading from cached content on the ISCSI vol but when writting it starts the first couple of seconds writting at 1GB/s then drops to 9MB/s and it stays there

if I disable primocache write happens at 102mb/s stables from start to end, so there is something wrong with ISCSI VOLS.
I just formated my computer yesterday as my main OS disk crashed.
SO I running windows 10 latest update.
Primocache latest version
and this is the config
Level 1 Cache Memory 0 MB
Level 2 cache Size MAX
BLock Size 4KB(Tried all the options performance same)
Enable defer Write
Latency 60 Sec
Write Mode Native
Any idea what I could change to fix the issue?
I have primocache only Level 1 cache on my OS Drive and works perfect the defer write.