ERROR: Not enough space

Now this is a very unspecific question. I'm trying to figure out what this message would mean.

Here is the story behind it:
I'm installing Oracle enterprise manager cloud control (12c r3) on Solaris 10 (5/09). Installer opens up, i enter all needed information and at the last step click Install. It immediately crashes with only "ERROR: Not enough space" written in log and console and nothing else.

Now, this could be java error or Solaris error? I'm thinking it's happening either when it starts to copy files or when it tries to launch a process that would do that.

What space is it referring to? disk (have ehough), swap (also), memory (yep)…

Any ideas are helpful.

Edit:
i found this exception in the oraInventory logs:

oracle.sysman.oii.oiic.OiicInstallAPIException: Not enough space
    at oracle.sysman.oii.oiic.OiicAPIInstaller.initInstallSession(OiicAPIInstaller.java:2165)
    at oracle.sysman.oii.oiic.OiicAPIInstaller.initOUIAPISession(OiicAPIInstaller.java:790)
    at oracle.sysman.install.oneclick.EMGCOUIInstaller.prepareForInstall(EMGCOUIInstaller.java:676)
    at oracle.sysman.install.oneclick.EMGCSummaryDlgonNext$1.run(EMGCSummaryDlgonNext.java:243)
    at java.lang.Thread.run(Thread.java:662)
    at oracle.sysman.install.oneclick.EMGCSummaryDlgonNext.actionsOnClickofNext(EMGCSummaryDlgonNext.java:1067)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at oracle.sysman.install.oneclick.EMGCUtil.performonClickOfNextForClass(EMGCUtil.java:399)
    at oracle.sysman.install.oneclick.EMGCUtil.performPageLevelValidationsForSilentInstall(EMGCUtil.java:367)
    at oracle.sysman.install.oneclick.EMGCInstaller.prepareForSilentInstall(EMGCInstaller.java:1459)
    at oracle.sysman.install.oneclick.EMGCInstaller.main(EMGCInstaller.java:1553)

disk status:

bash-3.00$ df -h /tmp
Filesystem             size   used  avail capacity  Mounted on
swap                   8.1G   2.7G   5.4G    33%    /tmp

bash-3.00$ df -h /u01
Filesystem             size   used  avail capacity  Mounted on
/                      275G    28G   244G    11%    /

swap:

root@gs12emcc # swap -s
total: 18306040k bytes allocated + 3837808k reserved = 22143848k used, 5712664k available