[jcifs] rcv_buf_size & snd_buf_size

Michael B Allen ioplex at gmail.com
Thu Oct 8 10:21:02 MDT 2009

[Please send all messages through the JCIFS mailing list.]

On Thu, Oct 8, 2009 at 4:40 AM, Stian Brattland <stian at brattland.no> wrote:
> Hi Michael,
> I have pasted in my testing code below.
> public class CopyTest {
>   private static final byte[] buffer  = new byte[60416];
>     public CopyTest() {
>       //I'm setting the client properties here in the constructor. However,
> regardless
>       //of the values i set here WireShark never reports package sizes above
> 16574 bytes.
>       System.setProperty("jcifs.smb.client.rcv_buf_size", "60416");
>       System.setProperty("jcifs.smb.client.snd_buf_size", "16644");

JCIFS properties are global and static and must be set before JCIFS
classes are loaded. To be sure that your settings are being honored
you must set them in main() or ideally via the
-Djcifs.properties=jcifs.prp commandline option.


>> On Wed, Oct 7, 2009 at 5:56 AM, Stian Brattland <stian at brattland.no>
>> wrote:
>>> Hi,
>>> I'm using WireShark to monitor the smb traffic between my application
>>> (which
>>> use JCifs) and a Samba server running on linux. All settings are the
>>> default
>>> ones.
>>> When i copy files using windows drag and drop, WireShare reports the
>>> following: Read AndX Request, FID: 0x14fe, 61440 bytes at offset (...).
>>> However, when
>>> i use the JCifs package, WireShare never reports package sizes above
>>> 16574.
>>> Regardless of wether i change the "jcifs.smb.client.snd_buf_size" or
>>> "jcifs.smb.client.rcv_buf_size", this package size never changes.
>>> I'm using System.setProperty() when i try to alter the buffer sizes. Have
>>> anyone else ever experienced this problem?
>> Hi Stian,
>> What does your JCIFS code look like? Maybe it's not using a larger buffer?
>> Note that a larger buffer does not equate to faster transfers. The
>> most important factor is getting as much data into each packet (e.g.
>> every other packet has 1 byte would be slow).
>> Mike

Michael B Allen
Java Active Directory Integration

More information about the jCIFS mailing list