Download performance is not linear

[blegay]

Hi,

It seems the download performance is not linear.
On a 7G+ file

It starts at 46 Mb/s
It finishes at 17 Mb/s

Plugin version 4.8.2 MacOS...

`
var $options : Object
$options:=New object
$options.HTTPGET:=1
$options.USE_SSL:="USESSL_ALL"
$options.SSL_VERIFYPEER:=2
$options.SSL_VERIFYHOST:=1
$options.CAINFO:="Macintosh HD:Users:ble:Library:Application Support:4D:com.ac-consulting:curllib-component:cacert.pem"
$options.WRITEDATA:="Macintosh HD:Users:ble:Downloads:test-download:"+Generate UUID+".tmp"

//https://curl.se/libcurl/c/CURLOPT_BUFFERSIZE.html

// https://curl.se/libcurl/c/CURLOPT_BUFFERSIZE.html
//$options.BUFFERSIZE:=5121024 //default value
$options.BUFFERSIZE:=101024*1024 // max value (faster download if connexion has big throughput) => makes de big difference

$options.URL:="https://example.com/" // a self signed AWS S3 url

var $vl_progressId : Integer
$vl_progressId:=Progress New
$options.PRIVATE:=JSON Stringify(New object("progressId"; $vl_progressId))

var $vx_curlRequestBody; $vx_curlResponseBody : Blob

var $vt_callbackMethod : Text
$vt_callbackMethod:="CURL_callback"

C_OBJECT($vo_curlResponse)
$vo_curlResponse:=cURL($options; $vx_curlRequestBody; $vx_curlResponseBody; $vt_callbackMethod)

Progress QUIT($vl_progressId)
`

I did not look at the code, but it may be related to the way data is appended to a file.

PS : not so important...

[miyako]

I did not look at the code, but it may be related to the way data is appended to a file.

that might be so. the plugin opens, seeks, writes, closes the file each time it gets data from the library.

[miyako]

that said, the download speed is measured internally by the library.
unless you are independently measuring the intervals, it might be because of something different.