![为什么 FileZilla 比 PSFTP 快得多?](https://linux22.com/image/660918/%E4%B8%BA%E4%BB%80%E4%B9%88%20FileZilla%20%E6%AF%94%20PSFTP%20%E5%BF%AB%E5%BE%97%E5%A4%9A%EF%BC%9F.png)
我正在使用 FileZilla 3.10.3 和 PSFTP 0.63 (PuTTY)。有人能帮我弄清楚为什么这两个客户端之间的吞吐量差异如此之大吗?这不可能只是 SFTP 协议的缺点,因为 FileZilla(和 WinSCP)要快得多!提前谢谢。
当使用 FileZilla 通过某种协议连接到同一台服务器时,我获得了“良好”的吞吐量;对于一个大文件,吞吐量约为 1.2MBPS。以下是日志:
Response: fzSftp started, protocol_version=2
Command: open "[email protected]" 22
Trace: Looking up host "ftp.themcorp.com"
Trace: Connecting to 222.22.111.33 port 22
Trace: We claim version: SSH-2.0-PuTTY_Local:_Mar_29_2015_12:25:15
Trace: Server version: SSH-2.0-9.99 sshlib: 8.1.0.0
Trace: Using SSH protocol version 2
Trace: Doing Diffie-Hellman group exchange
Trace: Doing Diffie-Hellman key exchange with hash SHA-1
Trace: Host key fingerprint is:
Trace: ssh-dss 1024 20:88:a6:92:fe:11:db:b4:9a:b5:9e:8b:5f:50:bb:77
Trace: Initialised AES-256 SDCTR client->server encryption
Trace: Initialised HMAC-SHA1 client->server MAC algorithm
Trace: Initialised AES-256 SDCTR server->client encryption
Trace: Initialised HMAC-SHA1 server->client MAC algorithm
Command: Pass: ********
Trace: Sent password
Trace: Access granted
Trace: Opening session as main channel
Trace: Opened main channel
Trace: Started a shell/command
Status: Connected to ftp.themcorp.com
Trace: CControlSocket::ResetOperation(0)
Status: Starting upload of c:\temp\test.zip
Command: cd "/Home/mecorp"
Response: New directory is: "/Home/mecorp"
Trace: CControlSocket::ResetOperation(0)
Trace: FileTransferSend()
Command: put "c:\temp\test.zip" "test.zip"
Status: local:c:\temp\test.zip => remote:/Home/mecorp/test.zip
Trace: FileTransferParseResponse()
Trace: CControlSocket::ResetOperation(0)
Status: File transfer successful, transferred 27,974,088 bytes in 21 seconds
当使用 PSFTP 连接到使用相同协议的同一服务器并传输相同文件时,我的吞吐量会慢得多。我估计大约为 150kbps(查看 Windows 7 任务管理器中的 I/O 字节)。以下是日志:
C:\temp>c:\d2\trunk\Util\psftp.exe -v -l mecorp -pw topsecret -P 22 ftp.themcorp.com
Looking up host "ftp.themcorp.com"
Connecting to 222.22.111.33 port 22
Server version: SSH-2.0-9.99 sshlib: 8.1.0.0
Using SSH protocol version 2
We claim version: SSH-2.0-PuTTY_Release_0.63
Doing Diffie-Hellman group exchange
Doing Diffie-Hellman key exchange with hash SHA-1
Host key fingerprint is:
ssh-dss 1024 20:88:a6:92:fe:11:db:b4:9a:b5:9e:8b:5f:50:bb:77
Initialised AES-256 SDCTR client->server encryption
Initialised HMAC-SHA1 client->server MAC algorithm
Initialised AES-256 SDCTR server->client encryption
Initialised HMAC-SHA1 server->client MAC algorithm
Using username "mecorp".
Sent password
Access granted
Opening session as main channel
Opened main channel
Started a shell/command
Connected to ftp.themcorp.com
Remote working directory is /Home/mecorp
psftp> put test.zip test.zip
local:test.zip => remote:/Home/mecorp/test.zip
psftp>
答案1
FileZilla 使用 PuTTY/psftp 源代码实现 SFTP。实际上 FileZilla 运行一个隐藏的 PSFTP 子进程。
但是它使用自己构建的 PSFTP(FzSFtp.exe
),其中进行了一些优化(和其他修改),包括:
- SFTP 传输队列为 4 MB(而 PSFTP 为 1 MB)
- 以更大的块分配内存(32 KB 对比 515 B)
- 使用大型网络缓冲区(SO_RCVBUF 为 4 MB,SO_SNDBUF 为动态大小 [使用 SIO_IDEAL_SEND_BACKLOG_QUERY])。PSFTP 保留系统默认设置。
FileZilla 还使用与 PuTTY (VS) 不同的编译器 (mingw),这可能会造成影响。
WinSCP 也基于 PSFTP 代码(尽管它在内部使用 PSFTP 代码,而不是在外部子进程中使用)并使用一组类似的优化。