2011/1/27 Vali Dragnuta <vali.dragn...@inode.ro>: > On Thu, 2011-01-27 at 08:59 -0500, Mircea Vutcovici wrote: >> 2011/1/25 Andrei Pascal <avpas...@gmail.com>: >> >> > >> > VMware iti freaca discul la greu, intrucat tine o copie pe disc a >> > memoriei VM-ului. Deci daca ai multe modificari in memorie (deci >> > masina folosita) normal c-o sa mearga greu intrucat astepti dupa disc. >> > >> >> >> Nu este o copie a memoriei VM-ului. Este doar un fisier care este >> mmap-at la memoria VM-ului. >> Fisierul ala e folosit cand nu mai ai memorie fizica pe host ca sa >> poata VMware sa faca swapping. >> Daca nu vrei sa se intample asta, trebuie sa nu ai overcommit la >> memoria de pe host. > > > Cel putin pe vmware server iti tine o copie a memoriei, nu doar ce nu > incape in memoria principala. Chiar si daca nu faci overcommit la > resurse. >
Nu cred ca cineva ar putea sa proiecteze un sistem care sa tina memoria fizica sincronizata cu un fisier swap pe un HDD si sa mai si poti sa faci ceva practic cu el. ESX 3 http://www.vmware.com/pdf/esx3_memory.pdf Swapping When you power on a virtual machine, a corresponding swap file is created and placed in the same location as the virtual machine configuration file (.vmx file). The virtual machine can power on only when the swap file is available. ESX Server hosts use swapping to forcibly reclaim memory from a virtual machine when no balloon driver is available. The balloon driver may be unavailable either because VMware Tools was never installed or because the driver has been disabled or is not running (for example, while the guest operating system is booting). For optimum performance, ESX Server uses the balloon approach whenever possible. However, swapping is used when the driver is temporarily unable to reclaim memory quickly enough to satisfy current system demands. Since the memory is being swapped out to disk, there is a rather significant performance penalty when this technique is used. Swapping is a reliable mechanism of last resort that a host uses only when necessary to reclaim memory. Standard-demand paging techniques swap pages back in when the virtual machine needs them. ESX 4 http://www.vmware.com/files/pdf/techpaper/vsp_41_perf_memory_mgmt.pdf However, hypervisor swapping is used as a last resort to reclaim memory from the virtual machine _______________________________________________ RLUG mailing list RLUG@lists.lug.ro http://lists.lug.ro/mailman/listinfo/rlug
