[jcifs] Performance Issue with jcifs and NetApp
Torsten Uhr
torsten.uhr at sql-ag.de
Fri May 31 03:15:30 MDT 2013
Hi,
our customer has discovered the IP addresses:
>Which systems are respectively 193.30.60.233 and 172.30.40.62 ?
->172.30.40.62 is the SMB the client is connecting to.
grztc001:/root # traceroute 172.30.40.62
traceroute to 172.30.40.62 (172.30.40.62), 30 hops max, 40 byte packets using UDP
1 vgmfas6a.customer.de (172.30.40.62) 2.192 ms 1.104 ms 0.302 ms
grztc001:/root # ping 172.30.40.62
PING 172.30.40.62 (172.30.40.62) 56(84) bytes of data.
64 bytes from 172.30.40.62: icmp_seq=1 ttl=255 time=0.334 ms
64 bytes from 172.30.40.62: icmp_seq=2 ttl=255 time=0.294 ms
64 bytes from 172.30.40.62: icmp_seq=3 ttl=255 time=0.285 ms
64 bytes from 172.30.40.62: icmp_seq=4 ttl=255 time=0.456 ms
64 bytes from 172.30.40.62: icmp_seq=5 ttl=255 time=0.535 ms
^C
--- 172.30.40.62 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 3996ms
rtt min/avg/max/mdev = 0.285/0.380/0.535/0.101 ms
> 193.30.60.233 is very suspicious!
grztc001:/root # traceroute 193.30.60.233
traceroute to 193.30.60.233 (193.30.60.233), 30 hops max, 40 byte packets using UDP
1 v320-cat2.customer.de (172.30.63.252) 0.314 ms 0.304 ms 0.273 ms
2 * * *
3 * * *
4 * * *
5 * * *
6 * * *
^C
grztc001:/root # ping 193.30.60.233
PING 193.30.60.233 (193.30.60.233) 56(84) bytes of data.
^C
--- 193.30.60.233 ping statistics ---
53 packets transmitted, 0 received, 100% packet loss, time 52415ms
nslookup resolved the name of the not responding server:
Trying "233.60.30.193.in-addr.arpa"
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 22794
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;233.60.30.193.in-addr.arpa. IN PTR
;; ANSWER SECTION:
233.60.30.193.in-addr.arpa. 84414 IN PTR vgm.government.com.
Received 79 bytes from 193.30.53.10#53 in 5 ms
The domain, the SMB user is authenticating to is 'VGM'. This is similar to the domain of the dead host. But this is only random!
Why jcifs is contacting this host is inexplicable. This host is not configured in the client.
>Can you run the same "netstat snapshots" while you are doing the same directory listing through the CIFS mountpoint ? (to compare)
grztc001:/TransConnect # smbclient //VGMVT01/VT-Logistik/ -U VGM/Transconnect
Enter VGM/Transconnect's password:
Domain=[VGM] OS=[Windows 5.0] Server=[Windows 2000 LAN Manager]
smb: \> dir
~snapshot DH 0 Fri May 31 00:00:26 2013
....
Dokumententitel.msg A 47616 Tue Apr 30 14:39:53 2013
61440 blocks of size 524288. 36388 blocks available
smb: \> exit
This are the results of the netstat
grztc001:/TransConnect # ./mytrace.sh
2013/05/31 10:09:04 -
2013/05/31 10:09:09 -
2013/05/31 10:09:14 - tcp 0 0 172.30.36.1:59061 172.30.40.62:445 VERBUNDEN 20569/smbclient
2013/05/31 10:09:19 - tcp 0 0 172.30.36.1:59061 172.30.40.62:445 VERBUNDEN 20569/smbclient
2013/05/31 10:09:24 - tcp 0 0 172.30.36.1:59061 172.30.40.62:445 VERBUNDEN 20569/smbclient
2013/05/31 10:09:29 - tcp 0 0 172.30.36.1:59061 172.30.40.62:445 VERBUNDEN 20569/smbclient
2013/05/31 10:09:34 -
2013/05/31 10:09:39 -
For Your interest, I have attached the client.
------------------------
Torsten Uhr
Email: torsten.uhr at sql-ag.de
Web : www.transconnect-online.de
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-----Ursprüngliche Nachricht-----
Von: jcifs-bounces at lists.samba.org [mailto:jcifs-bounces at lists.samba.org] Im Auftrag von André Warnier
Gesendet: Donnerstag, 30. Mai 2013 23:06
An: JCIFS Samba list
Betreff: Re: [jcifs] Performance Issue with jcifs and NetApp
Torsten Uhr wrote:
> Hi André,
>
> here are the results oft he netstat command before, while listing the folder and after that.
> It seems there are no unexpected connections.
A real network trace would be much more informative, but something below "does not smell right".
Which systems are respectively 193.30.60.233 and 172.30.40.62 ?
(I assume that the Linux client is 172.30.36.1).
It looks like a connection is attempted by 172.30.36.1 to 193.30.60.233:445, but
193.30.60.233 never responds. (See http://en.wikipedia.org/wiki/TCP_half-open).
It seems related to your directory listing, since both connections appear only during the listing. Maybe that is what slows things down here.
Can you run the same "netstat snapshots" while you are doing the same directory listing through the CIFS mountpoint ? (to compare)
Apart from that, we cannot get much further without a real packet trace, using one of the programs which Charles mentioned. You have enough information below to filter the packets which you need to capture.
Another way may be to provide a sample of the code which you use to do this directory listing. Maybe some java/cifs specialist here would spot some obvious mistake.
Don't count on it too much though : not many people feel like browsing through someone else's code to spot mistakes, and it is quite time-consuming. Providing a packet trace would be much better.
>
> BEFORE:
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
>
> WHILE:
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57740 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> tcp 0 1 172.30.36.1:57742 193.30.60.233:445 SYN_SENT 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> tcp 0 1 172.30.36.1:57743 193.30.60.233:445 SYN_SENT 27162/java
> tcp 0 0 172.30.36.1:57756 172.30.40.62:445 VERBUNDEN 27162/java
>
> AFTER:
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
> grztc001:/TransConnect # netstat -pn | grep -P ":(445|137|138|139)\s"
>
> With best regards
>
> Torsten Uhr
> Leiter Entwicklung TransConnect®
>
> Email: torsten.uhr at sql-ag.de
> Web : www.transconnect-online.de
> ·······················································
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>
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>
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>
> Diese E-Mail enthält vertrauliche und/oder rechtlich geschützte Informationen.
> Wenn Sie nicht der richtige Adressat sind oder diese E-Mail irrtümlich erhalten haben, informieren Sie bitte sofort den Absender und vernichten Sie diese Mail. Das unerlaubte Kopieren sowie die unbefugte Weitergabe dieser Mail oder Inhalte ist nicht gestattet.
>
> This e-mail may contain confidential and/or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and destroy this e-mail.
> Any unauthorized copying, disclosure or distribution of the material in this e-mail is strictly forbidden.
>
> ü SAVE PAPER - THINK BEFORE YOU PRINT
>
>
> -----Ursprüngliche Nachricht-----
> Von: jcifs-bounces at lists.samba.org
> [mailto:jcifs-bounces at lists.samba.org] Im Auftrag von André Warnier
> Gesendet: Mittwoch, 29. Mai 2013 17:00
> An: JCIFS Samba list
> Betreff: Re: [jcifs] Performance Issue with jcifs and NetApp
>
> Torsten Uhr wrote:
>> Hi André,
>>
>> thanks for Your quick reply.
>>
>>> Is that what happens ?
>> Exactly.
>>
>>> "NetApp fileserver" (whatever that is),
>> see: http://www.netapp.com/de/products/protocols/nas/cifs.aspx
>>
>>> do you have any way, on the NetApp server, to trace what is going on and see what the difference is when accessing these files from the one or the other type of client ?
>> I have pleased our customer to contact their operations to check out for any logs. At the moment their are only connection information but no logs.
>>
>>> Or alternatively, on the client system, to trace what is going on between that client and that NetApp server ?
>> I have told our customer to set the property 'jcifs.util.loglevel=10'. Are there any other tasks to enable logging in jcifs?
>> If i receive any further information, I will send it to You.
>
> Send it to the list, like before. I am not really an expert here, I was just trying to define the issue clearly.
>
> If the mounting of the CIFS filesystem works, and the access through that mountpoint is fast, that seems to eliminate any fundamental issue like network problems, or DNS problems, or authentication problems.
>
> So there must be something quite specific that slows down things when you access the files through the jcifs library. Which on the face of it looks a bit strange, because as far as I know the CIFS filesystem implementation under Linux is using much of the same codebase from samba.org.
> In that area, I am a bit over my head unfortunately.
>
> I would float a suspicion, but do not by any means consider this as a well-informed comment : maybe the way in which you are doing the access through the jcifs library is forcing it to create new connections all the time, resulting in a new authentication at each access ? That would probably slow down things quite a bit.
>
> The right tool to find out would be something like Wireshark, and get a network trace while you are reading a file (slowly) through the jcifs library.
> But you could just start such a (long) transfer, and then do a "netstat" on your Linux client. That should show at least the socket connections in use for that transfer.
> You are looking for port numbers :137, :138, :139 and :445.
> For example :
> netstat -pn | grep -P ":(445|137|138|139)\s"
>
>
>
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