# high cpu load with sftp-server



## neenz (Jan 12, 2009)

When our sftp server has more than 5 simultaneous connections the CPU usage jumps up 50% and rises exponentially with each connection. This is a busy server that sometimes has up to 50 simultaneous connections. Is their a kernel tweak or parameter that can be set to avoid this? We recently upgraded our sftp server to Freebsd 7.1 - but had this issue with 6.2 and 7.0 also. We don't seem to have this problem on a similar server running Centos 5.2.

-N


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## neenz (Jan 12, 2009)

*I should also add...*

We have 8 CPUs...

CPU: Intel(R) Xeon(R) CPU           E5430  @ 2.66GHz (2660.02-MHz K8-class CPU)
usable memory = 4281409536 (4083 MB)
avail memory  = 4112084992 (3921 MB)
ACPI APIC Table: <IBM    SERDEFNT>
FreeBSD/SMP: Multiprocessor System Detected: 8 CPUs
 cpu0 (BSP): APIC ID:  0
 cpu1 (AP): APIC ID:  1
 cpu2 (AP): APIC ID:  2
 cpu3 (AP): APIC ID:  3
 cpu4 (AP): APIC ID:  4
 cpu5 (AP): APIC ID:  5
 cpu6 (AP): APIC ID:  6
 cpu7 (AP): APIC ID:  7


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## neenz (Jan 16, 2009)

For example, this is the result of doing an ls on a directory containing 8,000 files:

Number of connections            total time to perform ls command     cpu usage per process
1                                             19 sec                                              80-99%
2                                             41 sec                                              80-99%
3                                             65 sec                                              80-99%
4                                             89 sec                                              80-99%


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