rrd

The rrd package allows you to read data from an RRD database.

Internally it uses librrd to import the binary data directly into R without exporting it to an intermediate format first.

For an introduction to RRD database, see https://oss.oetiker.ch/rrdtool/tut/rrd-beginners.en.html

Installation

Pre-requisites

In order to build the package from source you need librrd. Installing RRDtool from your package manager will usually also install the library.

In ubuntu:

sudo apt-get install rrdtool librrd-dev

In RHEL / CentOS:

sudo yum install rrdtool rrdtool-devel

Installing from CRAN

rrd is not yet on CRAN

Installing from github

And the development version from GitHub with:

# install.packages("devtools")
devtools::install_github("pldimitrov/rrd")

Example

In R:

library(rrd)

To describe the contents of an RRD file, use describe_rrd():

rrd_cpu_0 <- system.file("extdata/cpu-0.rrd", package = "rrd")

describe_rrd(rrd_cpu_0)
#> A RRD file with 10 RRA arrays and step size 60
#> [1] AVERAGE_60 (43200 rows)
#> [2] AVERAGE_300 (25920 rows)
#> [3] MIN_300 (25920 rows)
#> [4] MAX_300 (25920 rows)
#> [5] AVERAGE_3600 (8760 rows)
#> [6] MIN_3600 (8760 rows)
#> [7] MAX_3600 (8760 rows)
#> [8] AVERAGE_86400 (1825 rows)
#> [9] MIN_86400 (1825 rows)
#> [10] MAX_86400 (1825 rows)

To read an entire RRD file, i.e. all of the RRA archives, use read_rrd(). This returns a list of tibble objects:

cpu <- read_rrd(rrd_cpu_0)

str(cpu, max.level = 1)
#> List of 10
#>  $ AVERAGE60   :Classes 'tbl_df', 'tbl' and 'data.frame':    43199 obs. of  9 variables:
#>  $ AVERAGE300  :Classes 'tbl_df', 'tbl' and 'data.frame':    25919 obs. of  9 variables:
#>  $ MIN300      :Classes 'tbl_df', 'tbl' and 'data.frame':    25919 obs. of  9 variables:
#>  $ MAX300      :Classes 'tbl_df', 'tbl' and 'data.frame':    25919 obs. of  9 variables:
#>  $ AVERAGE3600 :Classes 'tbl_df', 'tbl' and 'data.frame':    8759 obs. of  9 variables:
#>  $ MIN3600     :Classes 'tbl_df', 'tbl' and 'data.frame':    8759 obs. of  9 variables:
#>  $ MAX3600     :Classes 'tbl_df', 'tbl' and 'data.frame':    8759 obs. of  9 variables:
#>  $ AVERAGE86400:Classes 'tbl_df', 'tbl' and 'data.frame':    1824 obs. of  9 variables:
#>  $ MIN86400    :Classes 'tbl_df', 'tbl' and 'data.frame':    1824 obs. of  9 variables:
#>  $ MAX86400    :Classes 'tbl_df', 'tbl' and 'data.frame':    1824 obs. of  9 variables:

Since the resulting object is a list of tibbles, you can easily work with individual data frames:

names(cpu)
#>  [1] "AVERAGE60"    "AVERAGE300"   "MIN300"       "MAX300"      
#>  [5] "AVERAGE3600"  "MIN3600"      "MAX3600"      "AVERAGE86400"
#>  [9] "MIN86400"     "MAX86400"

cpu[[1]]
#> # A tibble: 43,199 x 9
#>    timestamp              user     sys  nice  idle  wait   irq softirq
#>  * <dttm>                <dbl>   <dbl> <dbl> <dbl> <dbl> <dbl>   <dbl>
#>  1 2018-04-02 12:24:00 0.0104  0.00811     0 0.981     0     0       0
#>  2 2018-04-02 12:25:00 0.0126  0.00630     0 0.979     0     0       0
#>  3 2018-04-02 12:26:00 0.0159  0.00808     0 0.976     0     0       0
#>  4 2018-04-02 12:27:00 0.00853 0.00647     0 0.985     0     0       0
#>  5 2018-04-02 12:28:00 0.0122  0.00999     0 0.978     0     0       0
#>  6 2018-04-02 12:29:00 0.0106  0.00604     0 0.983     0     0       0
#>  7 2018-04-02 12:30:00 0.0147  0.00427     0 0.981     0     0       0
#>  8 2018-04-02 12:31:00 0.0193  0.00767     0 0.971     0     0       0
#>  9 2018-04-02 12:32:00 0.0300  0.0274      0 0.943     0     0       0
#> 10 2018-04-02 12:33:00 0.0162  0.00617     0 0.978     0     0       0
#> # ... with 43,189 more rows, and 1 more variable: stolen <dbl>

tail(cpu$AVERAGE60$sys)
#> [1] 0.0014390667 0.0020080000 0.0005689333 0.0000000000 0.0014390667
#> [6] 0.0005689333

To read a single RRA archive from an RRD file, use read_rra(). To use this function, you must specify several arguments that define the specific data to retrieve. This includes the consolidation function (e.g. "AVERAGE") and time step (e.g. 60), the end time. You must also specifiy either the start time, or the number of steps, n_steps.

In this example, you extract the average for 1 minute periods (step = 60), for one entire day (n_steps = 24 * 60):

end_time <- as.POSIXct("2018-05-02") # timestamp with data in example
avg_60 <- read_rra(rrd_cpu_0, cf = "AVERAGE", step = 60, n_steps = 24 * 60,
                     end = end_time)

avg_60
#> # A tibble: 1,440 x 9
#>    timestamp              user      sys  nice  idle     wait   irq softirq
#>  * <dttm>                <dbl>    <dbl> <dbl> <dbl>    <dbl> <dbl>   <dbl>
#>  1 2018-05-01 00:01:00 0.00458 0.00201      0 0.992 0            0       0
#>  2 2018-05-01 00:02:00 0.00258 0.000570     0 0.996 0            0       0
#>  3 2018-05-01 00:03:00 0.00633 0.00144      0 0.992 0            0       0
#>  4 2018-05-01 00:04:00 0.00515 0.00201      0 0.991 0            0       0
#>  5 2018-05-01 00:05:00 0.00402 0.000569     0 0.995 0            0       0
#>  6 2018-05-01 00:06:00 0.00689 0.00144      0 0.992 0            0       0
#>  7 2018-05-01 00:07:00 0.00371 0.00201      0 0.993 0.00144      0       0
#>  8 2018-05-01 00:08:00 0.00488 0.00201      0 0.993 0.000569     0       0
#>  9 2018-05-01 00:09:00 0.00748 0.000568     0 0.992 0            0       0
#> 10 2018-05-01 00:10:00 0.00516 0            0 0.995 0            0       0
#> # ... with 1,430 more rows, and 1 more variable: stolen <dbl>

And you can easily plot using your favourite packages:

library(ggplot2)
ggplot(avg_60, aes(x = timestamp, y = user)) + 
  geom_line() +
  stat_smooth(method = "loess", span = 0.125, se = FALSE) +
  ggtitle("CPU0 usage, data read from RRD file")

More information

For more information on rrdtool and the rrd format please refer to the official rrdtool documentation and tutorials.

You can read a more in-depth description of the package and more examples in this blog post.