The following graphs show the qmail-1.03 delivery behaviour, sending about 93,000 messages of a weekly newsletter list, injected by ezmlm-0.53 + ezmlm-idx-0.40.
The comparison is done for a delivery cycle with concurrencyremote set to 500, 250 and 150. The data is taken from three successive delivery cycles (each 1 week later, list has lost about 1% (i.e. 1000) of subscribers with each successive cycle).
All the graphs start at the time the message was injected by ezmlm.
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Number of concurrent remote deliveries per second
Number of finishing successful deliveries at that second (click images to enlarge) |
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This graph shows a snapshot of about 4000 seconds.
The peaks following the first delivery cycle most probably result from retransmits of the messages that couldn't be delivered during the first cycle. |
This graph is a zoom in to the first 1500 seconds of the same data as on the left side. |
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comparison of failed/deferred to successful deliveries
cut at 200 (y-axis), zoomed in to the first 1500 seconds (x-axis) (click images to enlarge) |
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| concurrencyremote 150 | concurrencyremote 250 | concurrencyremote 500 |
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| Numbers accounted to the second the delivery started | ||
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| Numbers accounted to the second the delivery ended. | ||
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duration of successful deliveries minimum/median/maximum
zoomed in to the first 1500 seconds (x-axis) numbers accounted to the second the delivery started (click images to enlarge) |
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| concurrencyremote 150 | concurrencyremote 250 | concurrencyremote 500 |
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| cut at 1000 seconds (y-axis) | ||
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| cut at 500 seconds (y-axis) | ||
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| cut at 200 seconds (y-axis) | ||
Some bandwidth information for the 150 data
This graph shows bandwidth consumption during the delivery. The graph is generated from 3-minute probes taken from the machine with the command
netstat -biI <eth_if>The x-axis is the time of the day (i.e. 12:00 p.m. to 15:00 p.m.), the y-axis is median bandwidth consumption per 3 minute intervals calculated to KBytes/second.
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Bandwidth consumption (KBytes/s)
(click images to enlarge) |
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| concurrencyremote 150 |
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Some additional information from the 500 data
To generate the following graphs I have counted the number of deliveries per each unique IP address and sorted them descending by this number. For the graphs I have used these data series and successivly summed up the number of IP addresses and the number of deliveries.
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x-axis: no of unique IP addresses (linear)
y-axis: percentage of deliveries (linear) |
x-axis: no of unique IP addresses (logarithmic)
y-axis: percentage of deliveries (linear) |
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x-axis: percentage of unique IP addresses (linear)
y-axis: percentage of deliveries (linear) |
System information
FreeBSD 3.4-RELEASE
qmail-1.03 + bigconcurrency modifications (concurrencyremote=500)
ezmlm-0.53 + ezmlm-idx-0.40
Thanks to
CPU: Pentium III (551.25-MHz 686-class CPU)
real memory = 268435456 (262144K bytes)
ahc0:
ahc0: aic7890/91 Wide Channel A, SCSI Id=7, 16/255 SCBs
da0 at ahc0 bus 0 target 0 lun 0
da0:
da0: 80.000MB/s transfers (40.000MHz, offset 31, 16bit), Tagged Queueing Enabled
da0: 30000MB (61440000 512 byte sectors: 255H 63S/T 3824C)
xl0: <3Com 3c905B-TX Fast Etherlink XL> rev 0x30 int a irq 12 on pci0.9.0
xl0: autoneg complete, link status good (full-duplex, 100Mbps)