sar stops reporting metrics for some of the network interfaces after creation of a significant amount of (virtual) network interfaces in Red Hat Enterprise Linux 7

Issue

After creating a significant amount of virtual network interfaces during the day, sar stops reporting metrics for some of the existing network interfaces.

E.g., on an example system, sar initially stores the following interfaces:

10:00:01 PM     IFACE   rxpck/s   txpck/s    rxkB/s    txkB/s   rxcmp/s   txcmp/s  rxmcst/s
10:10:02 PM     bond1     97.96     98.17     15.74      9.15      0.00      0.00      2.06
10:10:02 PM      ens2    208.54      0.00     14.56      0.00      0.00      0.00     89.14
10:10:02 PM      ens3     37.33     45.46      5.99      4.24      0.00      0.00      1.03
10:10:02 PM ovs-system      0.00      0.00      0.00      0.00      0.00      0.00      0.00
10:10:02 PM    br-int      0.00      0.00      0.00      0.00      0.00      0.00      0.00
10:10:02 PM    br-tun      0.00      0.00      0.00      0.00      0.00      0.00      0.00
10:10:02 PM     bond0      0.00      0.00      0.00      0.00      0.00      0.00      0.00
10:10:02 PM     eno49    208.53      0.00     14.56      0.00      0.00      0.00     89.11
10:10:02 PM    ens2d1      4.02      0.00      0.27      0.00      0.00      0.00      2.03
10:10:02 PM    ens3d1     14.10     11.81      1.32      7.93      0.00      0.00      2.04
10:10:02 PM        lo     34.86     34.86      2.25      2.25      0.00      0.00      0.00
10:10:02 PM br-management      4.02      0.20      0.22      0.03      0.00      0.00      0.00
10:10:02 PM  vlan1100      0.19      0.00      0.01      0.00      0.00      0.00      0.00
10:10:02 PM br-erogazione    210.09      0.00     11.79      0.00      0.00      0.00      0.00
10:10:02 PM  vlan1050     95.97     96.17     14.19      8.91      0.00      0.00      0.00
10:10:02 PM  vlan1000      5.08      6.05      0.37      6.91      0.00      0.00      0.00
10:10:02 PM   eno49d1     60.63     52.71      9.74      4.92      0.00      0.00      1.03
10:10:02 PM   docker0      0.00      0.00      0.00      0.00      0.00      0.00      0.00
10:10:02 PM  vlan1001      6.31      5.46      0.60      0.98      0.00      0.00      0.00
...
09:10:01 AM     bond1    176.91    154.45    319.02     14.97      0.00      0.00      2.06
09:10:01 AM      ens2 34038475.36      0.02 91908598.36      0.00      0.00      0.00 1212470.95
09:10:01 AM      ens3 580686.72 836561.23  93084.59  77674.73      0.00      0.00  13765.74
09:10:01 AM ovs-system      0.00      0.00      0.00      0.00      0.00      0.00      0.00
09:10:01 AM    br-int      0.00      0.00      0.00      0.00      0.00      0.00      0.00
09:10:01 AM    br-tun      0.00      0.00      0.00      0.00      0.00      0.00      0.00
09:10:01 AM     bond0      0.00      0.00      0.00      0.00      0.00      0.00      0.00
09:10:01 AM     eno49 34040730.65      0.03 91906792.77      0.00      0.00      0.00 1210627.87
09:20:01 AM vxlan_sys_4789   1438.08   1671.48    125.22   4751.02      0.00      0.00      0.00
09:20:01 AM     bond1 1964416.44 1822526.48 301665.17 173774.66      0.00      0.00  46228.63
09:20:01 AM      ens2 34054005.74      0.72 91949968.80      0.05      0.00      0.00 1213109.20
09:20:01 AM      ens3 581252.10 837525.41  93599.92  79952.92      0.00      0.00  13772.96
09:20:01 AM ovs-system      0.00      0.00      0.00      0.00      0.00      0.00      0.00
09:20:01 AM    br-int      0.00      0.00      0.00      0.00      0.00      0.00      0.00
09:30:01 AM vxlan_sys_4789   1034.13    741.20    680.13   2387.63      0.00      0.00      0.00
09:30:01 AM     bond1    287.48    398.62     36.35   1790.59      0.00      0.00      2.06
09:30:01 AM      ens2    219.51      1.06     15.41      0.08      0.00      0.00     95.46
09:30:01 AM      ens3     98.10    212.40     12.57    973.32      0.00      0.00      1.03
09:30:01 AM ovs-system      0.00      0.00      0.00      0.00      0.00      0.00      0.00
09:30:01 AM    br-int      0.00      0.00      0.00      0.00      0.00      0.00      0.00
09:40:01 AM vxlan_sys_4789    179.18    185.21     26.60     79.51      0.00      0.00      0.00
09:40:01 AM     bond1    123.48    126.87     19.97     67.41      0.00      0.00      2.06
09:40:01 AM      ens2    219.99      1.06     15.69      0.08      0.00      0.00     95.84
09:40:01 AM      ens3     44.19     60.39      7.19     33.54      0.00      0.00      1.03
09:40:01 AM ovs-system      0.00      0.00      0.00      0.00      0.00      0.00      0.00
09:40:01 AM    br-int      0.00      0.00      0.00      0.00      0.00      0.00      0.00
...

01:00:01 PM     bond1    110.00    113.51     17.47     68.13      0.00      0.00      2.06
01:00:01 PM      ens2    214.19      1.03     15.24      0.07      0.00      0.00     96.48
01:00:01 PM      ens3     42.06     54.12      6.66     35.62      0.00      0.00      1.03
01:00:01 PM ovs-system      0.00      0.00      0.00      0.00      0.00      0.00      0.00
01:00:01 PM    br-int      0.00      0.00      0.00      0.00      0.00      0.00      0.00
01:10:01 PM vxlan_sys_4789   7709.48   8119.80   1698.94  19468.74      0.00      0.00      0.00
01:10:01 PM     bond1 1966836.64 1825147.16 311068.47 185706.07      0.00      0.00  46224.36
01:20:01 PM vxlan_sys_4789    254.82    262.30     34.47    179.97      0.00      0.00      0.00
01:20:01 PM     bond1    118.21    123.10     27.96     99.25      0.00      0.00      2.06
01:30:01 PM vxlan_sys_4789    253.62    260.68     34.09    177.89      0.00      0.00      0.00
01:30:01 PM     bond1    118.69    123.32     28.08     95.99      0.00      0.00      2.06
01:40:01 PM vxlan_sys_4789    251.32    257.85     33.77    174.81      0.00      0.00      0.00
01:40:01 PM     bond1    119.06    123.99     24.23     93.28      0.00      0.00      2.06
01:50:01 PM vxlan_sys_4789    226.82    233.66     33.30    139.96      0.00      0.00      0.00
01:50:01 PM     bond1    124.14    128.90     29.08     96.55      0.00      0.00      2.06
02:00:01 PM vxlan_sys_4789    250.09    261.49     34.17    179.35      0.00      0.00      0.00
02:00:01 PM     bond1    127.41    132.35     29.13     99.02      0.00      0.00      2.06
02:10:01 PM vxlan_sys_4789    250.68    261.51     34.31    179.99      0.00      0.00      0.00
02:10:01 PM     bond1    124.11    128.99     29.06    100.01      0.00      0.00      2.06
02:20:01 PM vxlan_sys_4789    249.35    257.36     34.10    176.00      0.00      0.00      0.00
02:20:01 PM     bond1    119.45    124.10     28.22     94.86      0.00      0.00      2.06
02:30:01 PM vxlan_sys_4789    249.60    255.80     33.91    174.54      0.00      0.00      0.00
02:30:01 PM     bond1    117.73    122.39     23.96     93.53      0.00      0.00      2.06
02:40:01 PM vxlan_sys_4789  10482.40  10967.06   2026.29  21786.23      0.00      0.00      0.00
...

During the day, many virtual interfaces are created and sar from this moment on only reports those virtual interfaces:

09:50:01 PM qvb4a0a4c7c-89      0.53      0.02      0.04      0.00      0.00      0.00      0.00
09:50:01 PM qvo4a0a4c7c-89      0.02      0.53      0.00      0.04      0.00      0.00      0.00
09:50:01 PM qvbfa204299-07     27.63     26.58     37.76      1.21      0.00      0.00      0.00
09:50:01 PM qvofa204299-07     26.58     27.63      1.21     37.76      0.00      0.00      0.00
09:50:01 PM tapc630c03b-bb      0.04      3.24      0.00      0.22      0.00      0.00      0.00
09:50:01 PM qbref4f5ac7-68      3.46      0.00      0.19      0.00      0.00      0.00      0.00
09:50:01 PM tap9c679ada-f9      0.04      3.24      0.00      0.22      0.00      0.00      0.00
09:50:01 PM vxlan_sys_4789    582.06    593.47     47.68    642.40      0.00      0.00      0.00
09:50:01 PM tapeabbe9d7-82      0.04      2.94      0.00      0.42      0.00      0.00      0.00
09:50:01 PM tap8ab3368a-bb      0.04      0.52      0.00      0.04      0.00      0.00      0.00
09:50:01 PM tapdec2a999-10      1.01      2.26      0.06      0.16      0.00      0.00      0.00
09:50:01 PM qvb9743aafe-e2      3.45      0.02      0.24      0.00      0.00      0.00      0.00
09:50:01 PM qvo9743aafe-e2      0.02      3.45      0.00      0.24      0.00      0.00      0.00
09:50:01 PM tap98516bf7-bf      0.03      0.52      0.00      0.04      0.00      0.00      0.00
09:50:01 PM qvb69e975f4-f8      0.52      0.04      0.04      0.00      0.00      0.00      0.00
09:50:01 PM qvo69e975f4-f8      0.04      0.52      0.00      0.04      0.00      0.00      0.00
09:50:01 PM qvba4d6c7f9-35      9.55      0.04      0.63      0.00      0.00      0.00      0.00
09:50:01 PM qvoa4d6c7f9-35      0.04      9.55      0.00      0.63      0.00      0.00      0.00
09:50:01 PM qvb26868e69-29      2.95      0.03      0.42      0.00      0.00      0.00      0.00
09:50:01 PM qvo26868e69-29      0.03      2.95      0.00      0.42      0.00      0.00      0.00
09:50:01 PM tap72256b30-a2      0.04      2.94      0.00      0.42      0.00      0.00      0.00