135 reputation
6
bio website
location California
age
visits member for 3 years, 1 month
seen May 31 '13 at 17:52

Sep
15
awarded  Popular Question
May
4
awarded  Popular Question
Jan
12
awarded  Supporter
Jan
11
comment When the TCP engine decides to send an ACK?
For uploading, between two ACKs, there are around 22 frames transmitted. My guess is that, for uploading the delayed ACK is activated. Because, the time between ACKs is 0.6ms which is smaller than TCP_DELACK_MAX(2ms) and larger than TCP_DELACK_MIN(0.4ms). What you think?
Jan
10
comment When the TCP engine decides to send an ACK?
Yes, the main reason for this is the capabilities of CPU. My PC is capable of sending a packet every 12.5us average while the router sends a packet every 90us average. So, the uploading should be 7 time faster, but it didn't. That's why I think the ACK also has a quite important influence.
Jan
10
comment When the TCP engine decides to send an ACK?
This is exactly what I saw for the downloading, my PC ACKs after receiving two packets but not for the uploading. Besides, where the kernel's implementation for ACKing every other data packet?
Jan
10
asked When the TCP engine decides to send an ACK?
Jan
10
asked Needs help to understand the wireshark results of a data transferring
Dec
17
revised Why data sending is heavier for CPU than data receiving?
complement information
Dec
17
suggested approved edit on Why data sending is heavier for CPU than data receiving?
Dec
16
comment Why data sending is heavier for CPU than data receiving?
It's MBit, not Megabyte.
Dec
16
asked Why data sending is heavier for CPU than data receiving?
Nov
5
awarded  Editor
Nov
5
revised tftp server configuration under ubuntu, Access violation
added 282 characters in body
Nov
5
asked tftp server configuration under ubuntu, Access violation
Oct
26
awarded  Scholar
Oct
26
accepted Looking for advice to find the bottleneck of Samba server
Oct
26
comment Looking for advice to find the bottleneck of Samba server
Hi, I found the problems. In fact, it is the ehternet card in the PC which runs on 100mbit that put the limits. The arm in NAS router quick enough, so it has to wait in order not overflowing the ehternet card buffer. That's explain why there are so many default_idle. Thanks
Oct
25
comment Looking for advice to find the bottleneck of Samba server
Hi @adaptr, thanks for your answer. As you said SMB has considerable protocol overhead. But I am still not clear if this can explain the 37% of default_idle function. I think if the portion goes down to around 10%, the CPU can have more clocks available to handle smbd process which in turn increase its performance.
Oct
25
awarded  Student