Add sftp benchmark

README.md

@@ -50,7 +50,34 @@ Split views:
 - All vttest tests have passed except Tektronix 4014.
 - High performance, low memory, low latency.
 
-# Performance
+# Sftp Performance
+
+The hardware used for generating the data in these benchmarks was
+
+    windows 10 - 2.3 GHz Intel Core i5 and 8GB memory.
+
+**WindTerm 1.2, FileZilla 3.48.1, WinSCP 5.17.2 (Build 10278)** tests are performed on WSL(Ubuntu 18.04.2). 
+
+**All test data is for reference only.**
+
+- 5GB huge file (5,154,830 KB), generated by random data
+
+| | Download Time | Download Rate | Upload Time | Upload Rate |
+| --- | --- | --- | --- | --- |
+| WindTerm (Use high speed transfer) | **22s** | **234.3 MB/s** | **21s** | **245.5 MB/s** |
+| WindTerm | 37s | 139.3 MB/s | 43s | 119.9 MB/s |
+| FileZilla | 32s | 161.1 MB/s | 30s | 171.8 MB/s |
+| WinSCP | 81s | 63.7 MB/s | 91s | 56.7 MB/s |
+
+- 4400 files, 16 folders (107,042 KB), unzipped from [vim-7.4.1049.zip](https://github.com/vim/vim/archive/v7.4.1049.zip)
+
+| | Download Time | Download Rate | Upload Time | Upload Rate |
+| --- | --- | --- | --- | --- |
+| WindTerm | **32s** | **3.4 MB/s** | **10s** | **10.7 MB/s** |
+| FileZilla | 48s | 2.2 MB/s | 35s | 3.1 MB/s |
+| WinSCP | 42s | 2.6 MB/s | 12s | 8.9 MB/s |
+
+# Terminal Performance
 
 The hardware used for generating the data in these benchmarks was